RFR(M): JDK-8165500: TestJpsJar shouldn't jar all test.classpath directories

[Dmitry Samersoff]

(* Resending, Any reviewers? *)

Everybody,

Please, review:

http://cr.openjdk.java.net/~dsamersoff/JDK-8165500/webrev.02/

I refactored the test to improve stability and simplify further
debugging.

Testing: rbt

PS: Diffs is messy, so pleas look at raw files.

-Dmitry

-- 
Dmitry Samersoff
Oracle Java development team, Saint Petersburg, Russia
* I would love to change the world, but they won't give me the sources.