Add button and Capabilities to the list of MockFirmata users.
Rewrite ping tests to use MockFirmata and not use serial data. However, I'm not %100 confident in the change event tests. It's no worse then it was before but the behavior seems suspect.
Update pir tests to use MockFirmata and FakeTimers
Linting and leftover vars.
Rewrite sensor.js to use fakeTimers and mockFirmata