- sensor_baro.msg use SI (pressure in Pascals)
- update all barometer drivers to publish directly and remove PX4Barometer helper
- introduce baro cal (offset) mainly as a mechanism to adjust
relative priority
- commander: add simple baro cal that sets baro offsets to align with
GPS altitude (if available)
- create new sensors_status.msg to generalize sensor reporting
- this was an experiment to casually monitor sensor offsets relative to temperature, but now that all calibration offsets can be adjusted post-flight the stored temperature can be misleading
- deleting to save a little bit of flash (and storing the temperature wasn't useful)
Claudio Micheli