v3 FLARM stratux release

Thanks to @0x74-0x62 for rebasing to latest master (v1.5b2):

• Check changelog https://github.com/cyoung/stratux/releases
• FLARM debug logging is only enabled when DEBUG is enabled

NOTE: The v3 radio does not support FLARM at the moment since it requires a new firmware on the radio.

v2 FLARM stratux release

Based on v1.4r5-flarm release:

• merge latest changes from master (e.g. reenabling GLONASS and Galileo support for ublox8)
• introduce GDL90 ownship geometric altitude switch to allow using GPS height above WGS-84 ellipsoid like specified in the GDL90 specification
• estimate barometric altiude from FLARM GPS height since traffic reports in GDL90 expect barometric altitude

First FLARM stratux release

Based on v1.4r5 release:

• Add FLARM support
• Updated to include fixes for GPYes2
• Fixed missing libjpeg/libconfig