Multithreaded TBS now functional

mt_tbs.py now has the following capabilities:

* Specify trace files, core count, and explicit schedule.
* Use single trace file to create multiple threads.
* Multi-core works fine.
* Detailed output of what happened at the end of the run.

Missing features:
* Different base addresses for threads reusing the same trace file.
* Config file (currently config is hard-coded).