RFE: Use satellite compass instead of IMU as source of heading

[mgrouch]

They are getting cheaper and not subject to magnetic interference

Example:

https://holybro.com/products/h-rtk-unicore-um982

UM982. Can work without RTK just by using two antennas. Produces regular NMEA 0183 stream with some added sentences for Heading, best position estimate and orientation. With high rate.

Thanks