Add tests for user login
Add tests for user login

The --stderr flag is needed to get these tests working
on the command line, e.g.:
  cake test --stderr Test/Case/Controller/UsersControllerTest.php

Tatoeba/tatoeba2,Tatoeba/tatoeba2,Tatoeba/tatoeba2,Tatoeba/tatoeba2,Tatoeba/tatoeba2