Merge pull request #269 from PX4/new_led_status

src/drivers/px4io/px4io.cpp

src/modules/commander/commander.c

src/modules/commander/state_machine_helper.c

src/modules/px4iofirmware/mixer.cpp

src/modules/px4iofirmware/protocol.h

src/modules/px4iofirmware/registers.c

src/modules/px4iofirmware/safety.c

src/modules/uORB/topics/actuator_controls.h