title: Plug in django-allauth as endpoint in django-rest-framework
body: <p>I'm using django-allauth on my website for social logins. I also have a REST API powered by django-rest-framework that serves as the backend of a mobile app. Is there a way I can directly plug in allauth's authentication backend to the REST api so that I can validate (and register) users who use Facebook login in the mobile app?</p>
  
  <p>To clarify: The Facebook login part is handled by native SDKs. I need an endpoint that works like <code>POST /user</code> (that is, creates a new user), but takes Facebook oauth token as input instead of email/password etc.</p>