Remove insecure user_session route

[jniles]

In several places in bhima, we use the following code to download the user details

   dependencies.user = {
     query : '/user_session'
   };

This is poor practice for many reasons: it is insecure, brittle, and we have the user session available immediately with the SessionService without sending an extra HTTP request. We should remove instances of the above code in bhima.