a way to force the junit runner to stop when there is a test failure

I'm not sure if this is an acceptable solution, and I *didn't* add any test cases for this, but it's at least some progress on a **3 year old** request. http://jira.codehaus.org/browse/SUREFIRE-580

 - uses pleaseStop() from the RunNotifier, along with a config property in the pom
 - doesn't work with Scalatest <=2.1.5 (it works, it's just not very graceful - there is an open issue with Scalatest that is being resolved)
 - I'm not sure if TestNG has an equivalent, but it would probably be a similar modification to the Provider