Remove references to the harness's call stack in back traces

Prior to this when NOT running in `--debug` mode the harness's call
stack would be removed from any stack trace to clarify the calling
methods within a test. This extends that functionality to `--debug`
mode.
Merge pull request #491 from justinstoller/bug/master/QE71-alwasy_remove_harness_stack

Remove references to the harness's call stack in back traces