When requesting to add a new component to a container, the error response should contain proper error codes

Currently, the error response does not contain error code, which facilitates front-end to display localized error messages:

{
   "success":false,
   "message":"Node '/hst:hst/hst:configurations/hap-preview/hst:workspace/hst:containers/homepage/main' cannot be locked due to someone else who has the lock (possibly a descendant or ancestor that is locked).",
   "errorCode":null,
   "data":[

   ]
}

It should container proper error code, so the frond-end can use these code to localize error messages.

The current error messages in CM 3.x are attached.

Updated:

• Wrapper ExtResponseRepresentation should be removed because this API is used by AngularJs app
• Change the API interface from @Path("/create/{itemUUID}") to @Path("/{itemUUID}") to align with REST APIs standardization