Adding strobe detection.

Adding strobe detection.

- This requires that no strobes are floating.
  On Rev. 0.4, pins D1 and D0 of the teensy must be manually connected to GND
  On Rev. 0.2, when not using the 18 pin connector, pin C6 and C7 must be manually connected to GND
- Added a problem keys cli command, this is very useful to see which keys were disabled at startup because they looked like test points
  (the fastest way to get the keys to re-enable is to take off a keycap and jiggle the spring)