RFR: 8207855: Make applications/jcstress invoke tests in batches

[Christian Tornqvist]

Please review this change that changes the way we invoke the jcstress tests, using batch invocation rather than individual invocation. The time savings are significant, in the Oracle test farm the time executing these tests on Linux x64 went from 182h to 8h. 

TestGenerator.java: Changed it to not add @run tags for all the individual tests, but rather group them by package name. Removed ‘-m default’ from the list of arguments passed to jcstress, since ‘default’ is the default mode when nothing has been specified. Timeout has been adjusted for dealing with the 3-4h it takes to run some of the bigger groups.

TEST.groups: Created jcstress_partX groups to be able to execute these tests efficiently in parallel in our test farm.

The rest of the files have been generated by TestGenerator. The change has been tested in Mach 5.

Webrev: http://cr.openjdk.java.net/~ctornqvi/webrev/8207855/webrev.00/ <http://cr.openjdk.java.net/~ctornqvi/webrev/8207855/webrev.00/>
Bug: https://bugs.openjdk.java.net/browse/JDK-8207855 <https://bugs.openjdk.java.net/browse/JDK-8207855>

Thanks,
Christian