Update dependencies

Update
+ SBT 0.13.0 -> 0.13.5
+ Play 2.2.0 -> 2.2.3
+ Unicorn 0.4.1 -> 0.5.2

Additionally rewrite whole code. I think there should be add plays Global object with DI and application orchestration.
Default ScalaDoc. Also, `{ }` are not necessary here.