Added code to the ServiceCode.pys MetadataObjectForURL() function. This function is required in order for many Plex clients to function correctly. (Plex/Web, iOS, Roku, Win8, etc) The new code, like the rest of the ServiceCode, relies on the session_id which is passed to it from the main plugin code. Without this session_id, there is no way for the ServiceCode to access the CR API.

This change now allows most of the Plex clients to function properly.