Keep track of FT sensor warnings/faults

The saturation status of each of the 6 strain gauges in the FT sensor is reported as a 7th byte in the returned torque packet if any of the gauges have experienced saturation since the most recent tare. This data is presently discarded by the FT sensor code in lbt. But it would be nice to keep track of the gauge status so the user has an opportunity to re-tare at an appropriate time for their application. 7th byte format: /* Check for gage saturation

• RBGGGGGG
• R = Re-tare suggested
• B = Bad data present
• GGGGGG = Latched saturated gages */