Refactor gulp code out
Grunt support
Drop Safari until https://code.google.com/p/selenium/issues/detail?id=7933 is fixed (Safari 7.1 is a no go)
Refactor SubSuite running logic into SubSuite...
Mishmash of changes:

* Consistent license headers.
* Documented All The Things.
* `mocha/run.js` now limits the number of tests that can concurrently _run_
  (not just test).
* A ton of stability fixes.