ug-2815 fix build test due to concurrency, included old pr #273 & #274 from apigee/ug-stack

1. PR apigee/ug-stack #273 (PortFinder fix)
2. PR apigee/ug-stack #274 (rm cold counterStore test)
3. Fix .pom to upgrade dependency to C* 1.2.12 
4. Fix .pom to use jamm when starting C* in test (otherwise OOM)
5. Use countdown latch to ensure job got executed in (some) Job Scheduler Test
6. Fix TestJobListener.blockTillDone in job listener and javadoc
7. Fix TestJobListenerTest
8. Fix BatchCountParallelismTest on properly awaitTermination and wait till batch submission executed before counting.
9. Fix concurrency counting issues in various implementers of the ResponseHandler in the AbstractQueueResourceIT by using AtomicInteger (not completed)