Add a worker for reporting global stats to Prometheus

Fixes #1789

data/model/organization.py

@@ -137,6 +137,10 @@ def get_organizations():
   return User.select().where(User.organization == True, User.robot == False)
 
 
+def get_active_org_count():
+  return get_organizations().count()
+
+
 def add_user_as_admin(user_obj, org_obj):
   try:
     admin_role = TeamRole.get(name='admin')