* Added CrossPlatformDeathPenalty that doesn't rely on signals
* Updated `SimpleWorker`'s `death_penalty_class` to utilize `CrossPlatformDeathPenalty` to allow use on Windows machines
* Changed `CrossPlatformDeathPenalty` to `TimerDeathPenalty`
* Removed overridden `death_penalty_class` in `SimpleWorker` until feature matures
* Added section in testing.md explaining how to utilize `SimpleWorker` on Windows OS
* Replaced usage of chatting with .format for python 3.5 compatibility
* Add tests for new timeout feature
* Explicitly set defaults.CALLBACK_TIMEOUT
* Implemented cross-thread method of raising errors by using ctypes
* Finished writing tests for new TimerDeathPenalty
Michael Hill