Introduce class that contains all enabled test rules

For this to happen ScalaVersionTestRule has to extend MethodRule
directly.
Add ExceptionWrapper test rule
Revert "Run tests on the compiler thread to make them more stable."

Wrapping all tests in ask calls is ugly.

This reverts commit 8cc9d71578dcfb046f1cfbec7c83840203e76e13.
Execute all tests in ReusingPrinterTest in one ask call
Update to JUnit 4.11
Update P2 repository to kepler
Merge pull request #65 from sschaef/add-junit-rule

Add junit rule