Add code to disable throttle if we are on the ground and in FBW_B or higher.  We believe we are on the ground if speed < 5 and alt < 5.  Also check that we are not trying to perform a takeoff.

These files are not generated by cmake. They are necessary for
the make based build to work. To build using this method
type make in the directoy such as ArudPlane/ArduCopter. Make
sure that you do not call cmake in the ArduPlane etc directory
as this will overwrite this Makefile with the autogenerated cmake
version. Cmake should be called from withing a build directory.

added Position mode
removed
Added back in the accelerometer experiment
Added filter_result boolean to enable filter on the fly

Also updated cmake files.

Conflicts:
	ArduBoat/ArduBoat.pde
	ArduBoat/CMakeLists.txt
	ArduRover/ArduRover.pde
	ArduRover/CMakeLists.txt
	apo/CMakeLists.txt
	apo/apo.pde

lowered Rate Error max in loiter

restored 42 alt hold code
removed throttle timer, replaced with safer constant
increased alt control range
reformatted nav_rate calls
removed unused simple mode defines
set alt hold home to 10m
tuned down rateP to .13 from .14 for broader application.

Reverted to simpler, safer timer code for throttle hold