sensors: support for Futaba RC failsafe
commander: bug fixed in failsafe
sensors: code style fixed
fix usage of wrong value for max airspeed parameter
Merge pull request #506 from thomasgubler/tecs_airspeedmax_param_fix

fix usage of wrong value for max airspeed parameter
fix vehicle_airspeed_poll logic: _tecs.enable_airspeed was not called before on valid airspeed
Merge pull request #507 from thomasgubler/airspeed_poll

fix vehicle_airspeed_poll logic
multirotor_att_control: use PID lib for yaw rate control
multirotor_att_control: style fixes, cleanup
Merge remote-tracking branch 'upstream/master'
initialize _vel_dot and _STEdotErrLast
Fix to cancel pending callbacks for closing ORB topics
Fixed typo, added testing - previous corner case now cleanly prevented
Merge pull request #509 from PX4/orb_fix

Orb fix
Matrix and Vector printing cleanup
Merge branch 'master' of github.com:PX4/Firmware
Hotfix for mag calibration
Hotfix: Check for out of range accel values
Smaller hotfixes for att pos estimator
Merge branch 'master' into rc_failsafe