- if not in air the accel noise is doubled
- if landed don't init unless GPS velocity is non-negligible
- when inactive continue seeding with EKF gyro bias
- reset yaw estimator if GPS fusion is stopped
- don't store unnecessary IMU copy in class, pass it through where required
- remove custom pi constants
- remove unused fields from ahrs_ekf_gsf (vel_NE, fuse_gps, accel_dt)
- explicitly initialize everything in header
- apply PX4 code style
- set GPS velocity before yaw estimator update, not after
bresch