Refactoring extension->user artefact fixed

app/app.py

@@ -220,9 +220,9 @@ async def amiSetHint(context, user, hint):
   Returns:
     boolean: True if DialplanUserAdd action was successfull, False overwise
   '''
-  reply = await manager.send_action({'Action': 'DialplanUserAdd',
+  reply = await manager.send_action({'Action': 'DialplanExtensionAdd',
                                      'Context': context,
-                                     'User': user,
+                                     'Extension': user,
                                      'Priority': 'hint',
                                      'Application': hint,
                                      'Replace': 'yes'})