ISPN-4029 Reworked NotifyingFutureTest
ISPN-4897 Make all server CLI commands lowercase
ISPN-4802 Make HotRodConcurrentStartTest more robust

* Since the method starts Hot Rod servers, it should take
responsibility to kill them too.
* Increased timeout for creating Hot Rod server.
* Use fork() method so that thread naming is correctly set.
* Finally, use Try() as a cleaner way to deal with failures
of either of Hot Rod server startups.