Commented out parts of the PWM output code for the APM so that Outputs 3-8 can be used as digital pins for temperature sensors, software serial, etc.
Renamed Satcom to SatcomMessage because I will only deal with providing the message content. Josh will handle the rest of the Satcom.
Added the necessary code to the APM file to read the PPM signal from the RC controller. This hasn't been tested on an APM2.6.