Add the missing cut operation (see #112)

Author: fritzmg

contao/dca/tl_style_manager.php

@@ -50,6 +50,10 @@
                 'href'          => 'act=paste&mode=copy',
                 'icon'          => 'copy.svg'
             ],
+            'cut' => [
+                'href'          => 'act=paste&mode=cut',
+                'icon'          => 'cut.svg'
+            ],
             'delete' => [
                 'href'          => 'act=delete',
                 'icon'          => 'delete.svg',