Include default match statement to CaseClassCodec macro

Also add compile warnings to the build.

JAVA-4319

Author: jakehschwartz

bson-scala/src/main/scala/org/mongodb/scala/bson/codecs/macrocodecs/CaseClassCodec.scala

@@ -350,7 +350,7 @@ private[codecs] object CaseClassCodec {
                   val instanceValue = value.asInstanceOf[${classType}]
                   ..${writeClassValues(fields, ignoredFields(classType))}"""
         }.toSeq
-      }
+      } :+ cq"""_ => throw new BsonInvalidOperationException("Unexpected class type: " + className)"""
       q"""
         writer.writeStartDocument()
         this.writeClassFieldName(writer, className, encoderContext)

build.gradle

@@ -128,6 +128,15 @@ configure(scalaProjects) {
 
     tasks.withType(ScalaCompile) {
         scalaCompileOptions.deprecation = false
+        if(scalaVersion.startsWith("2.13")) {
+            scalaCompileOptions.additionalParameters = [
+                    "-feature",
+                    "-unchecked",
+                    "-language:reflectiveCalls",
+                    "-Wconf:cat=deprecation:ws,any:e",
+                    "-Xlint:strict-unsealed-patmat"
+            ]
+        }
     }
 
     tasks.withType(GenerateModuleMetadata) {