improved file module GUI: now pushing a notification when markdown was copied

Signed-off-by: Stephan Richter <s.richter@srsoftware.de>

translations/src/main/resources/en.json

@@ -173,6 +173,7 @@
   "logout_user": "logout {user}",
 
   "markdown_code": "Markdown-Code",
+  "Markdown has been copied to clipboard!": "Markdown has been copied to clipboard!",
   "markdown_supported": "Markdown & <a target=\"_blank\" href=\"https://plantuml.com\">Plantuml</a> supported!",
   "MANAGE_LOGIN_SERVICES": "manage login services",
   "member": "member",
@@ -205,6 +206,7 @@
   "month": "month",
   "move_to_top": "move to top level",
   "must_not_be_empty": "must not be empty",
+  "my files": "my files",
 
   "name": "Name",
   "net_price": "net price",