diff --git a/package-lock.json b/package-lock.json
index 53c11e5..091abe7 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,6 +1,6 @@
 {
   "name": "custom-dual-listbox",
-  "version": "1.0.1",
+  "version": "1.0.2",
   "lockfileVersion": 1,
   "requires": true,
   "dependencies": {
@@ -164,11 +164,18 @@
       }
     },
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-      "version": "5.2.9",
-      "resolved": "https://registry.npmjs.org/@angular/core/-/core-5.2.9.tgz",
-      "integrity": "sha512-cvHBJGtasrIoARvbLFyHaOsiWKVwMNrrSTZLwrlyHP8oYzkDrE0qKGer6QCqyKt+51hF53cgWEffGzM/u/0wYg==",
+      "version": "11.0.5",
+      "resolved": "https://registry.npmjs.org/@angular/core/-/core-11.0.5.tgz",
+      "integrity": "sha512-XAXWQi7R3ucZXQwx9QK5jSKJeQyRJ53u2dQDpr7R5stzeCy1a5hrNOkZLg9zOTTPcth/6+FrOrRZP9SMdxtw3w==",
       "requires": {
-        "tslib": "1.9.0"
+        "tslib": "^2.0.0"
+      },
+      "dependencies": {
+        "tslib": {
+          "version": "2.4.0",
+          "resolved": "https://registry.npmjs.org/tslib/-/tslib-2.4.0.tgz",
+          "integrity": "sha512-d6xOpEDfsi2CZVlPQzGeux8XMwLT9hssAsaPYExaQMuYskwb+x1x7J371tWlbBdWHroy99KnVB6qIkUbs5X3UQ=="
+        }
       }
     },
     "@angular/forms": {
@@ -385,6 +392,7 @@
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       "integrity": "sha1-u13KOCu5TwXhUZQ3PRb9O6HKEQ0=",
       "dev": true,
+      "optional": true,
       "requires": {
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         "readable-stream": "2.3.5"
@@ -480,7 +488,8 @@
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       "resolved": "https://registry.npmjs.org/asn1/-/asn1-0.2.3.tgz",
       "integrity": "sha1-2sh4dxPJlmhJ/IGAd36+nB3fO4Y=",
-      "dev": true
+      "dev": true,
+      "optional": true
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     "asn1.js": {
       "version": "4.10.1",
@@ -506,7 +515,8 @@
       "version": "0.2.0",
       "resolved": "https://registry.npmjs.org/assert-plus/-/assert-plus-0.2.0.tgz",
       "integrity": "sha1-104bh+ev/A24qttwIfP+SBAasjQ=",
-      "dev": true
+      "dev": true,
+      "optional": true
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@@ -540,7 +550,8 @@
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       "resolved": "https://registry.npmjs.org/asynckit/-/asynckit-0.4.0.tgz",
       "integrity": "sha1-x57Zf380y48robyXkLzDZkdLS3k=",
-      "dev": true
+      "dev": true,
+      "optional": true
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       "version": "2.0.3",
@@ -566,13 +577,15 @@
       "version": "0.6.0",
       "resolved": "https://registry.npmjs.org/aws-sign2/-/aws-sign2-0.6.0.tgz",
       "integrity": "sha1-FDQt0428yU0OW4fXY81jYSwOeU8=",
-      "dev": true
+      "dev": true,
+      "optional": true
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     "aws4": {
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       "resolved": "https://registry.npmjs.org/aws4/-/aws4-1.6.0.tgz",
       "integrity": "sha1-g+9cqGCysy5KDe7e6MdxudtXRx4=",
-      "dev": true
+      "dev": true,
+      "optional": true
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     "babel-code-frame": {
       "version": "6.26.0",
@@ -840,6 +853,7 @@
       "resolved": "https://registry.npmjs.org/boom/-/boom-2.10.1.tgz",
       "integrity": "sha1-OciRjO/1eZ+D+UkqhI9iWt0Mdm8=",
       "dev": true,
+      "optional": true,
       "requires": {
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       }
@@ -1332,6 +1346,7 @@
       "resolved": "https://registry.npmjs.org/combined-stream/-/combined-stream-1.0.6.tgz",
       "integrity": "sha1-cj599ugBrFYTETp+RFqbactjKBg=",
       "dev": true,
+      "optional": true,
       "requires": {
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       }
@@ -1423,7 +1438,8 @@
       "version": "1.1.0",
       "resolved": "https://registry.npmjs.org/console-control-strings/-/console-control-strings-1.1.0.tgz",
       "integrity": "sha1-PXz0Rk22RG6mRL9LOVB/mFEAjo4=",
-      "dev": true
+      "dev": true,
+      "optional": true
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     "constants-browserify": {
       "version": "1.0.0",
@@ -1609,6 +1625,7 @@
       "resolved": "https://registry.npmjs.org/cryptiles/-/cryptiles-2.0.5.tgz",
       "integrity": "sha1-O9/s3GCBR8HGcgL6KR59ylnqo7g=",
       "dev": true,
+      "optional": true,
       "requires": {
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       }
@@ -1691,6 +1708,7 @@
       "resolved": "https://registry.npmjs.org/dashdash/-/dashdash-1.14.1.tgz",
       "integrity": "sha1-hTz6D3y+L+1d4gMmuN1YEDX24vA=",
       "dev": true,
+      "optional": true,
       "requires": {
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@@ -1699,7 +1717,8 @@
           "version": "1.0.0",
           "resolved": "https://registry.npmjs.org/assert-plus/-/assert-plus-1.0.0.tgz",
           "integrity": "sha1-8S4PPF13sLHN2RRpQuTpbB5N1SU=",
-          "dev": true
+          "dev": true,
+          "optional": true
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@@ -1805,13 +1824,15 @@
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       "resolved": "https://registry.npmjs.org/delayed-stream/-/delayed-stream-1.0.0.tgz",
       "integrity": "sha1-3zrhmayt+31ECqrgsp4icrJOxhk=",
-      "dev": true
+      "dev": true,
+      "optional": true
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       "resolved": "https://registry.npmjs.org/delegates/-/delegates-1.0.0.tgz",
       "integrity": "sha1-hMbhWbgZBP3KWaDvRM2HDTElD5o=",
-      "dev": true
+      "dev": true,
+      "optional": true
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@@ -2381,7 +2402,8 @@
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       "resolved": "https://registry.npmjs.org/extend/-/extend-3.0.1.tgz",
       "integrity": "sha1-p1Xqe8Gt/MWjHOfnYtuq3F5jZEQ=",
-      "dev": true
+      "dev": true,
+      "optional": true
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     "extend-shallow": {
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@@ -2452,7 +2474,8 @@
       "version": "1.3.0",
       "resolved": "https://registry.npmjs.org/extsprintf/-/extsprintf-1.3.0.tgz",
       "integrity": "sha1-lpGEQOMEGnpBT4xS48V06zw+HgU=",
-      "dev": true
+      "dev": true,
+      "optional": true
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     "fast-deep-equal": {
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@@ -2579,13 +2602,15 @@
       "version": "0.6.1",
       "resolved": "https://registry.npmjs.org/forever-agent/-/forever-agent-0.6.1.tgz",
       "integrity": "sha1-+8cfDEGt6zf5bFd60e1C2P2sypE=",
-      "dev": true
+      "dev": true,
+      "optional": true
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     "form-data": {
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       "resolved": "https://registry.npmjs.org/form-data/-/form-data-2.1.4.tgz",
       "integrity": "sha1-M8GDrPGTJ27KqYFDpp6Uv+4XUNE=",
       "dev": true,
+      "optional": true,
       "requires": {
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         "combined-stream": "1.0.6",
@@ -2682,7 +2707,8 @@
         "ansi-regex": {
           "version": "2.1.1",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "aproba": {
           "version": "1.1.1",
@@ -2733,7 +2759,8 @@
         "balanced-match": {
           "version": "0.4.2",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "bcrypt-pbkdf": {
           "version": "1.0.1",
@@ -2748,6 +2775,7 @@
           "version": "0.0.9",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "inherits": "2.0.3"
           }
@@ -2756,6 +2784,7 @@
           "version": "2.10.1",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "hoek": "2.16.3"
           }
@@ -2764,6 +2793,7 @@
           "version": "1.1.7",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
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             "concat-map": "0.0.1"
@@ -2772,7 +2802,8 @@
         "buffer-shims": {
           "version": "1.0.0",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
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         "caseless": {
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@@ -2789,12 +2820,14 @@
         "code-point-at": {
           "version": "1.1.0",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "combined-stream": {
           "version": "1.0.5",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
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           }
@@ -2802,22 +2835,26 @@
         "concat-map": {
           "version": "0.0.1",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
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         "console-control-strings": {
           "version": "1.1.0",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
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         "core-util-is": {
           "version": "1.0.2",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
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         "cryptiles": {
           "version": "2.0.5",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "boom": "2.10.1"
           }
@@ -2857,7 +2894,8 @@
         "delayed-stream": {
           "version": "1.0.0",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
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           "version": "1.0.0",
@@ -2889,7 +2927,8 @@
         "extsprintf": {
           "version": "1.0.2",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "forever-agent": {
           "version": "0.6.1",
@@ -2911,12 +2950,14 @@
         "fs.realpath": {
           "version": "1.0.0",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "fstream": {
           "version": "1.0.11",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "graceful-fs": "4.1.11",
             "inherits": "2.0.3",
@@ -2972,6 +3013,7 @@
           "version": "7.1.2",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "fs.realpath": "1.0.0",
             "inflight": "1.0.6",
@@ -2984,7 +3026,8 @@
         "graceful-fs": {
           "version": "4.1.11",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "har-schema": {
           "version": "1.0.5",
@@ -3012,6 +3055,7 @@
           "version": "3.1.3",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "boom": "2.10.1",
             "cryptiles": "2.0.5",
@@ -3022,7 +3066,8 @@
         "hoek": {
           "version": "2.16.3",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
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         "http-signature": {
           "version": "1.1.1",
@@ -3039,6 +3084,7 @@
           "version": "1.0.6",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "once": "1.4.0",
             "wrappy": "1.0.2"
@@ -3047,7 +3093,8 @@
         "inherits": {
           "version": "2.0.3",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
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           "version": "1.3.4",
@@ -3059,6 +3106,7 @@
           "version": "1.0.0",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
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           }
@@ -3072,7 +3120,8 @@
         "isarray": {
           "version": "1.0.0",
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-          "dev": true
+          "dev": true,
+          "optional": true
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@@ -3145,12 +3194,14 @@
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           "version": "1.27.0",
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-          "dev": true
+          "dev": true,
+          "optional": true
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           "version": "2.1.15",
           "bundled": true,
           "dev": true,
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@@ -3159,6 +3210,7 @@
           "version": "3.0.4",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
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@@ -3166,12 +3218,14 @@
         "minimist": {
           "version": "0.0.8",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
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         "mkdirp": {
           "version": "0.5.1",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
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@@ -3226,7 +3280,8 @@
         "number-is-nan": {
           "version": "1.0.1",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
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         "oauth-sign": {
           "version": "0.8.2",
@@ -3244,6 +3299,7 @@
           "version": "1.4.0",
           "bundled": true,
           "dev": true,
+          "optional": true,
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@@ -3273,7 +3329,8 @@
         "path-is-absolute": {
           "version": "1.0.1",
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-          "dev": true
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+          "optional": true
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         "performance-now": {
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@@ -3284,7 +3341,8 @@
         "process-nextick-args": {
           "version": "1.0.7",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
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           "version": "1.4.1",
@@ -3322,6 +3380,7 @@
           "version": "2.2.9",
           "bundled": true,
           "dev": true,
+          "optional": true,
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@@ -3366,6 +3425,7 @@
           "version": "2.6.1",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
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           }
@@ -3373,7 +3433,8 @@
         "safe-buffer": {
           "version": "5.0.1",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
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           "version": "5.3.0",
@@ -3397,6 +3458,7 @@
           "version": "1.0.9",
           "bundled": true,
           "dev": true,
+          "optional": true,
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           }
@@ -3430,6 +3492,7 @@
           "version": "1.0.2",
           "bundled": true,
           "dev": true,
+          "optional": true,
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@@ -3440,6 +3503,7 @@
           "version": "1.0.1",
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           "dev": true,
+          "optional": true,
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@@ -3454,6 +3518,7 @@
           "version": "3.0.1",
           "bundled": true,
           "dev": true,
+          "optional": true,
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           }
@@ -3468,6 +3533,7 @@
           "version": "2.2.1",
           "bundled": true,
           "dev": true,
+          "optional": true,
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@@ -3523,7 +3589,8 @@
         "util-deprecate": {
           "version": "1.0.2",
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+          "optional": true
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@@ -3552,7 +3619,8 @@
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           "version": "1.0.2",
           "bundled": true,
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       "integrity": "sha1-XB+x8RdHcRTwYyoOtLcbPLD9MXE=",
       "dev": true,
+      "optional": true,
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@@ -3579,6 +3648,7 @@
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       "integrity": "sha1-LANAXHU4w51+s3sxcCLjJfsBi/c=",
       "dev": true,
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@@ -3646,6 +3716,7 @@
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       "integrity": "sha1-Xv+OPmhNVprkyysSgmBOi6YhSfo=",
       "dev": true,
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@@ -3654,7 +3725,8 @@
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           "integrity": "sha1-8S4PPF13sLHN2RRpQuTpbB5N1SU=",
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       "integrity": "sha1-4Ob+aijPUROIVeCG0Wkedx3iqLk=",
-      "dev": true
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@@ -3880,6 +3953,7 @@
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       "integrity": "sha1-B4REvXwWQLD+VA0sm3PVlnjo4cQ=",
       "dev": true,
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@@ -3908,7 +3982,8 @@
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       "integrity": "sha1-ILt0A9POo5jpHcRxCo/xuCdKJe0=",
-      "dev": true
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@@ -4107,6 +4182,7 @@
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       "integrity": "sha1-33LiZwZs0Kxn+3at+OE0qPvPkb8=",
       "dev": true,
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@@ -4533,7 +4609,8 @@
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       "integrity": "sha1-5HnICFjfDBsR3dppQPlgEfzaSpo=",
-      "dev": true
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+      "optional": true
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@@ -4578,7 +4655,8 @@
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-      "dev": true
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@@ -4682,7 +4760,8 @@
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       "integrity": "sha1-tIDIkuWaLwWVTOcnvT8qTogvnhM=",
-      "dev": true
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+      "optional": true
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     "json-schema-traverse": {
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@@ -4704,7 +4783,8 @@
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       "resolved": "https://registry.npmjs.org/json-stringify-safe/-/json-stringify-safe-5.0.1.tgz",
       "integrity": "sha1-Epai1Y/UXxmg9s4B1lcB4sc1tus=",
-      "dev": true
+      "dev": true,
+      "optional": true
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     "json3": {
       "version": "3.3.2",
@@ -4746,6 +4826,7 @@
       "resolved": "https://registry.npmjs.org/jsprim/-/jsprim-1.4.1.tgz",
       "integrity": "sha1-MT5mvB5cwG5Di8G3SZwuXFastqI=",
       "dev": true,
+      "optional": true,
       "requires": {
         "assert-plus": "1.0.0",
         "extsprintf": "1.3.0",
@@ -4757,7 +4838,8 @@
           "version": "1.0.0",
           "resolved": "https://registry.npmjs.org/assert-plus/-/assert-plus-1.0.0.tgz",
           "integrity": "sha1-8S4PPF13sLHN2RRpQuTpbB5N1SU=",
-          "dev": true
+          "dev": true,
+          "optional": true
         }
       }
     },
@@ -5473,7 +5555,8 @@
           "version": "2.2.1",
           "resolved": "https://registry.npmjs.org/ansi-styles/-/ansi-styles-2.2.1.tgz",
           "integrity": "sha1-tDLdM1i2NM914eRmQ2gkBTPB3b4=",
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "caseless": {
           "version": "0.11.0",
@@ -5487,6 +5570,7 @@
           "resolved": "https://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
           "integrity": "sha1-qBFcVeSnAv5NFQq9OHKCKn4J/Jg=",
           "dev": true,
+          "optional": true,
           "requires": {
             "ansi-styles": "2.2.1",
             "escape-string-regexp": "1.0.5",
@@ -5548,7 +5632,8 @@
           "version": "2.0.0",
           "resolved": "https://registry.npmjs.org/supports-color/-/supports-color-2.0.0.tgz",
           "integrity": "sha1-U10EXOa2Nj+kARcIRimZXp3zJMc=",
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "tunnel-agent": {
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@@ -5610,6 +5695,7 @@
       "resolved": "https://registry.npmjs.org/npmlog/-/npmlog-4.1.2.tgz",
       "integrity": "sha512-2uUqazuKlTaSI/dC8AzicUck7+IrEaOnN/e0jd3Xtt1KcGpwx30v50mL7oPyr/h9bL3E4aZccVwpwP+5W9Vjkg==",
       "dev": true,
+      "optional": true,
       "requires": {
         "are-we-there-yet": "1.1.4",
         "console-control-strings": "1.1.0",
@@ -5642,7 +5728,8 @@
       "version": "0.8.2",
       "resolved": "https://registry.npmjs.org/oauth-sign/-/oauth-sign-0.8.2.tgz",
       "integrity": "sha1-Rqarfwrq2N6unsBWV4C31O/rnUM=",
-      "dev": true
+      "dev": true,
+      "optional": true
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     "object-assign": {
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@@ -7186,6 +7273,7 @@
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       "integrity": "sha1-ZUEYTMkK7qbG57NeJlkIJEPGYZg=",
       "dev": true,
+      "optional": true,
       "requires": {
         "hoek": "2.16.3"
       }
@@ -7346,6 +7434,7 @@
       "resolved": "https://registry.npmjs.org/sshpk/-/sshpk-1.14.1.tgz",
       "integrity": "sha1-Ew9Zde3a2WPx1W+SuaxsUfqfg+s=",
       "dev": true,
+      "optional": true,
       "requires": {
         "asn1": "0.2.3",
         "assert-plus": "1.0.0",
@@ -7361,7 +7450,8 @@
           "version": "1.0.0",
           "resolved": "https://registry.npmjs.org/assert-plus/-/assert-plus-1.0.0.tgz",
           "integrity": "sha1-8S4PPF13sLHN2RRpQuTpbB5N1SU=",
-          "dev": true
+          "dev": true,
+          "optional": true
         }
       }
     },
@@ -7531,7 +7621,8 @@
       "version": "0.0.5",
       "resolved": "https://registry.npmjs.org/stringstream/-/stringstream-0.0.5.tgz",
       "integrity": "sha1-TkhM1N5aC7vuGORjB3EKioFiGHg=",
-      "dev": true
+      "dev": true,
+      "optional": true
     },
     "strip-ansi": {
       "version": "3.0.1",
@@ -7777,6 +7868,7 @@
       "resolved": "https://registry.npmjs.org/tough-cookie/-/tough-cookie-2.3.4.tgz",
       "integrity": "sha512-TZ6TTfI5NtZnuyy/Kecv+CnoROnyXn2DN97LontgQpCwsX2XyLYCC0ENhYkehSOwAp8rTQKc/NUIF7BkQ5rKLA==",
       "dev": true,
+      "optional": true,
       "requires": {
         "punycode": "1.4.1"
       }
@@ -8253,6 +8345,7 @@
       "resolved": "https://registry.npmjs.org/verror/-/verror-1.10.0.tgz",
       "integrity": "sha1-OhBcoXBTr1XW4nDB+CiGguGNpAA=",
       "dev": true,
+      "optional": true,
       "requires": {
         "assert-plus": "1.0.0",
         "core-util-is": "1.0.2",
@@ -8263,7 +8356,8 @@
           "version": "1.0.0",
           "resolved": "https://registry.npmjs.org/assert-plus/-/assert-plus-1.0.0.tgz",
           "integrity": "sha1-8S4PPF13sLHN2RRpQuTpbB5N1SU=",
-          "dev": true
+          "dev": true,
+          "optional": true
         }
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     },
@@ -9443,6 +9537,7 @@
       "resolved": "https://registry.npmjs.org/wide-align/-/wide-align-1.1.2.tgz",
       "integrity": "sha512-ijDLlyQ7s6x1JgCLur53osjm/UXUYD9+0PbYKrBsYisYXzCxN+HC3mYDNy/dWdmf3AwqwU3CXwDCvsNgGK1S0w==",
       "dev": true,
+      "optional": true,
       "requires": {
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       }
diff --git a/package.json b/package.json
index d1331ed..e3720b0 100644
--- a/package.json
+++ b/package.json
@@ -24,7 +24,7 @@
     "@angular/animations": "^5.2.3",
     "@angular/common": "^5.2.3",
     "@angular/compiler": "^5.2.3",
-    "@angular/core": "^5.2.3",
+    "@angular/core": "^11.0.5",
     "@angular/forms": "^5.2.3",
     "@angular/http": "^5.2.3",
     "@angular/platform-browser": "^5.2.3",