New redirect strategy

I change the way the redirect strategy works.
The redirects from authenticate/logout actions are now callbacks.
This way the user can overwrite the default callback and decide **exactly** what to should happen.

ping @Ocramius

closes #479
closes #476
closes #473
closes #469
Should this now be $routeMatch, as referenced on L27?  Although having said that, L105 still references the router although I'm not sure where this is set now?