Hotfix: Off-by-one fix in overflow check
Merge branch 'master' of github.com:PX4/Firmware
arming: added PWM_SERVO_SET_ARM_OK and PWM_SERVO_CLEAR_ARM_OK

these new ioctls allow for the flight code to tell the IO board that
arming can proceed
Hotfix: install the firmware .bin files as well as the .px4 bundles until we have a chance to fix the px4io uploader.