RangeFinder: remove raw_value, orientation variables

This saves 10bytes of RAM
RangeFinder: remove raw_value from SharpGP2Y
PulsedLightRFinder: read method returns int16_t
MaxsonarRFinder: convert_raw returns int16_t
MaxsonarI2C: read method returns int16_t
Maxsonar Test: remove raw from output to user
AP_Motors: motor_to_channel_map moved to progmem
AP_MotorsTri: motor_to_channel_map moved to progmem
SingleCopter: motor_to_channel_map moved to progmem
TradHeli: motor_to_channel_map moved to progmem
MotorsMatrix: motor_to_channel_map moved to progmem