INT-3144 Fix JMX Tests Timing Issue

Really only an issue with the queue channel test, but change
all tests to use CountDownLatches instead of relying on Thread.sleep().
INT-3144 Fix JMX Tests Timing Issue

Really only an issue with the queue channel test, but change
all tests to use CountDownLatches instead of relying on Thread.sleep().
Merge pull request #890 from garyrussell/INT-3144

INT-3144 Fix JMX Tests Timing Issue