standalone ap_ahrs: remove AP_GPS library

* supertrain is going to turn these bits into a slurry.
standalone_apahrs: small simple AP_GPS lib w/ shim

* keeps compatibility with AP_AHRS without any crap we dont need
apwrapper: support for new AP_GPS
ivory-px4-hardware: stub out gps driver testbed
test app for ublox-gps-test
ivory-px4-hw: simple ublox UBX frame parser works
ivory-px4-hw: ublox parser works.