Create better test summary

[benmccann]

Right now, it just lists the class that had a failing test eventhough there are several tests in that class. It would be much more helpful if it listed the failed method names as well.

[error] Failed: Total 293, Failed 1, Errors 0, Passed 280, Skipped 12
[error] Failed tests:
[error]         com.connectifier.MyTest

This is the built-in, default summary from sbt. It is a generic summary that supports all frameworks and thus doesn't try to be too fancy. In the new test interface supported by 0.13, test frameworks can provide their own summary that will override sbt's.

https://github.com/sbt/test-interface/blob/master/src/main/java/sbt/testing/Runner.java#L87