Campus users
The users wich are in a campus

GET /v2/campus_users
Return all the campus users

GET /v2/users/:user_id/campus_users
Return all the campus users of the given User

GET /v2/campus_users/:id
Get a campus user

POST /v2/campus_users
Create a campus user

POST /v2/users/:user_id/campus_users
Create a campus user for the given User

POST /v2/campus_users/:id/set_as_primary