Refactor auth code

* don't use __container__
* register it as a factory on container and inject into routes and
  controller
* avoid afterSignIn errors by checking on hooksTarget, ApplicationRoute
  should register itself as a hooksTarget
* keep user info on auth
Remove afterSignIn hook from actions in AuthRoute

This is a leftover from previous version of auth code. The purpose of
this code was to redirect to index if we're on auth route and user is
already signed in. This may happen only when we use autoSignIn which is
synchronuous, so it should be fine to just check if user is signed in
and redirect to index there.
Remove auth logic from redirect in Travis.Route

Auth check in redirect duplicates beforeModel logic
Bring back afterSignIn and afterSignIn as actions sent to controller

It seems that there is more use cases to cover with this behaviour, for
example when someone enters /auth directly and logs in from there.
Merge pull request #282 from travis-ci/ps-auth-refactoring

Refactor auth code