Unexplained issues seen in this deployment.

- Range finder failure.
- Load Cell failure. (may be related to the range-finder, they share a component on the spring controller board)
- Power Converter firmware should more gracefully handle a failed range-finder condition.
- Heave-cone controller:  on 2 occasions, it has failed to respond to an open/close command.  I saw it once, as did Francois.  Works after power-cycle using "tether off/tether on" in spring controller
- Heave-cone occasionally stops updating yaw position, seems to keep communicating
- Nav440 occasionally starts to think it's spinning. Power cycle fixes.
- Nav440 occasionally stops updating lat/lon. Power cycle fixes.