title: last_login field is not updated when authenticating using Tokenauthentication in Django Rest Framework
body: <p>I'm working in a project which relies in a Django User model and TokenAuthentication under DjangoRestFramework</p>
  
  <p>I was requested to get last login datetime for each user and I've realized that this field is not getting updated when I call the authentication REST endpoint.</p>
  
  <p>Is this a known fact? Am I missing something I must do in order to get that field updated each time the token authentication is called?</p>
  
  <p>Thanks</p>