Add North/East/Down velocity feature

SlashDevin released this 18 Mar 18:44

· 30 commits to master since this release

58879f5

Add new Velocity North/East/Down members
- new configuration item in GPSfix_cfg.h
- values and validity flags added to gps_fix
- printed by trace_all
- parsed from UBX NAV_VELNED message

Assets 2