Add Plex XML shortcuts to libraries, users, and sync headers

plexpy/webserve.py

@@ -277,6 +277,8 @@ class WebInterface(object):
     def return_plex_xml_url(self, endpoint='', plextv=False, **kwargs):
         kwargs['X-Plex-Token'] = plexpy.CONFIG.PMS_TOKEN
         base_url = 'https://plex.tv' if plextv else plexpy.CONFIG.PMS_URL
+        if '{machine_id}' in endpoint:
+            endpoint = endpoint.format(machine_id=plexpy.CONFIG.PMS_IDENTIFIER)
         return base_url + endpoint + '?' + urllib.urlencode(kwargs)
 
     @cherrypy.expose