Copter: bug fix to 50hz logging rate

Caught by Emile Castelnuovo
AC_PosControl: update _pos_error if it is being limited

This fixes a bug that causes 10hz throttle noise.
AP_NavEKF: fixed log replay code

also added BARO and ARSP messages
AP_Baro: added alternative setHIL interface

uses pressure and temperature for better log replay
RC_Channel: fixed comment on enable_aux_servos()

thanks to Mike McCauley for spotting
AP_Airspeed: added setHIL() method

useful for log playback
AP_HAL_FLYMAPLE RCOutput.cpp: enable_ch no longer resets servo

FLYMAPLERCOutput::enable_ch incorrectly reset the servo to 0, which caused
servo twitching once per second when RC_Channel_aux::enable_aux_servos
enabled each channel.
AntennaTracker: update to build with latest libraries

AntennaTracker has not been maintained as other parts of the system and
libraries have been modernised. This patch at least gets it to the stage where
it compiles and runs in SITL. Also added Tools/autotest/sim_antennatracker.sh
to run in SITL
AntennaTracker: sim_antennatracker.sh does make clean sitl