Major Description
It would be nice to add the ability to produce incoming messages back out to a configurable topic in TestPerformanceTask.
This will allow us to simulate collector.send lag in TestSamzaContainerPerformance with a MockSystemProducer (if we want to). It will also allow us to run TestPerformanceTask against real data in a real grid, and have it output to some topic to show real throughput when producing messages.