Ammended pin assignment for EAGLE_A3Pro, rebuild targets
Merge https://github.com/jfitter/FlightStab

did not merge in the hex files. will be rebuilding after the next change.
rebuilt jfitter's changes and added deadband filter for master_gain.

- update target files (a3pro pin mapping update, and master_gain deadband filter)
- move pdf file to Docs/EagleA3Pro Guide.cdr