AirborneCodeReorg

Current airborne code has gone a little bit out of control and is in deep need of a reorganization.

Fixed wing airframes have makefile directly in them - we can't change anything in the airborne code without breaking everybody's airframe

Booz uses "susbsystem" Makefiles

 include $(PAPARAZZI_SRC)/conf/autopilot/booz2_common.makefile
 include $(CFG_BOOZ)/subsystems/booz2_radio_control_ppm.makefile
 include $(CFG_BOOZ)/subsystems/booz2_actuators_mkk.makefile
 include $(CFG_BOOZ)/subsystems/booz2_imu_b2v1.makefile

This is the Makefile part of a booz vehicle using a booz2 IMU, mikrokopter actuators and ppm radio control