closes #347 modified stress test to support multiple roots inorder to av...

...oid collisions
I ran the updated stress test on my machine.  While running the tests, the "Total at root" was high during the tests and incorrect at the end (it was 487590 when it should have been 48759).  The problem is that this line is converting totalSeen & totalWait to strings and appending them rather than adding the numbers & converting the sum to a string.  It should be changed to: `System.out.println("Total at root : " + (stats.totalSeen + stats.totalWait));`

Everything else looks good!