Merge pull request #132 from PX4/#111-px4io-integrated-mixing

apps/drivers/boards/px4io/px4io_internal.h

apps/drivers/drv_mixer.h

apps/drivers/hil/hil.cpp

apps/drivers/px4fmu/fmu.cpp

apps/drivers/px4io/px4io.cpp

apps/drivers/px4io/uploader.cpp

apps/px4io/Makefile

apps/px4io/comms.c

apps/px4io/controls.c

apps/px4io/dsm.c

apps/px4io/mixer.cpp

apps/px4io/protocol.h

apps/px4io/px4io.c

apps/px4io/px4io.h

apps/px4io/safety.c

apps/px4io/sbus.c

apps/systemcmds/mixer/mixer.c

apps/systemlib/mixer/mixer.cpp

apps/systemlib/mixer/mixer.h

apps/systemlib/mixer/mixer_group.cpp