Eliminate a lot of the if cases in create_user by separating them out. Add a limit to the number of users which can be created based on the license. Add support for creating and loading licenses.

endpoints/callbacks.py

@@ -87,7 +87,7 @@ def github_oauth_callback():
     # try to create the user
     try:
       to_login = model.create_federated_user(username, found_email, 'github',
-                                             github_id)
+                                             github_id, set_password_notification=True)
 
       # Success, tell analytics
       analytics.track(to_login.username, 'register', {'service': 'github'})