Play 2.2 compatibility fixes

These should be enough for working play 2.2 support. I also cleaned up the build files a bit. I removed the hardcoded local maven repo publishing as SBT now has a `publishM2` task that should to it better.

I also had to remove the `scct` dependency as it does not support sbt 0.13 currently. I found no code references to it, so I assume it was used for manually checking test coverage, correct?