Allow non-async authorizedAction (and break fewer code)

The current implementation switch to play 2.2 forces the use of Future[SimpleResult] in authorizedAction.

Therefore code like

    authorizedAction(authority) { Ok("success") }

breaks.

Plain play actions can be used this way. You can either write

    Action(bodyParser) { Ok("success") }

or if you need it asynchonously, you write

    Action.async(bodyParser) { Future.successful(Ok("success")) }

This change allows this for autorizedAction:

    authorizedAction(authority) { Ok("success") }
    authoritedAction.async(authority) { Future.successful(Ok("success")) }

Furthermore, with this change, old code - that is already using non-asynchronous authorizedActions - is not breaking anymore.