update to devise 3

The new token logic for confirmation emails requires users to use @token
instead if @user.confirmation_token in mailer views.

Note that this commit removes the token_authenticatable option for
devise. If this is still needed, we need to find a solution as described
here:

  https://gist.github.com/josevalim/fb706b1e933ef01e4fb6
  https://github.com/aaronchi/simple_token_authentication
  http://blog.plataformatec.com.br/2013/08/devise-3-1-now-with-more-secure-defaults/
devise: sign in user after account confirmation

This is potentially unsafe, but removes the necessity to login after
the link in the email was clicked.
spec: remove some tests related to authentication_token
Remove token authentication.

We will use regular server sessions/cookies and oauth if required.
create new backbone models for devise3
Update currentUser after login/logout.
Set view model to currentUser and remove unused userName parameter.
Remove some dead code in application controller.
Set version number for devise.
Use new user registration model for sign up.
Explicitly set allowed request methods to make devise accept json (see https://github.com/plataformatec/devise/issues/2209) and by usin
Cleanup api signin/signout helpers (they are actually just json calls to devise).

- Also disable session spec for now as devise json login cannot be tested like this with spec.
Drop column authentication_token.
Remove accidental line break.
Fix jasmine specs.
Merge pull request #61 from cnrk/feature/devise

Feature/devise
Merge branch 'master' into 30-website-redesign

Conflicts:
	app/controllers/application_controller.rb
	app/views/home/index.html.haml