This adds the possibility to use offboard velocity control in the body
frame and not just the NED (world) frame.
The frame is set in the set_position_target_local_ned message and passed
on to mc_pos_control in the position_setpoint topic.
* Fix jmavsim HITL simulation of MAV_CMD_DO_REPOSITION in the case where you have no radio attached to the PX4 and so you have disabled RC link loss for that reason (set NAV_RCL_ACT = 0) but you still want the jmavsimulation to work. The line of code changed here causes failsafe RTL to kick in without this fix.
* Add altitude hold option using Z position control, while doing velocity control on vx and vy.
* Fix style and rebase issues
Daniel Agar
Julian Oes
Lorenz Meier
sander
Jimmy Johnson
Lorenz Meier
Roman
Andreas Antener
Thomas Gubler