Implement slick-play
Switch to cache. Get authtokens working in the cache.

TODO: Rebuild secureaction
Cache up and running for LandingPage and FeaturedGames.
TokenController renamed SessionController.
LeagueClient actorref migrated into session.
AuthenticatedRequest now uses token to retrieve from the cache.
Merge branch 'feature/move_to_play-slick' into develop
Add unique username on index.
Drop seed data.
Merge branch 'release/0.0.4'