UT: State Machine

Unit Testing for the State Machine. Run various values (nominal, boundary, fault, etc.) through and ensure (assert) that the correct state transitions occur.

@ezraboley has a test here that would be a great reference point: https://github.com/badgerloop-software/pod-embedded/blob/master/embedded/examples/stateTest.c

We'll want these tests (and others) updated & done using GTest