Copter: disable Log_Read if no CLI
DataFlash: avoid CLI functions on APM2 for copter
Copter: disable dump_log when no APM2
Copter: remove unused var from ekf check
Copter: of-loiter unavailable if OPTFLOW not enabled

of-loiter was small but still present even when optflow was disabled
Copter: disable parachute and rally on APM1
Copter: remove empty Telemetry.pde
Copter: remove unused local var from Flip
Copter: remove ch6 tuning of INAV_TC

Users normally never change these parameters and if by chance they do want
to, they can set them before flying
InertialNav: remove accessor to set time_constants
DataFlash: typo fix in ListAvailableLogs
BaroGlitch: increase default ok distance to 5m

When taking off some copters hove a sudden baro altitude dip of 4m
Copter: clarify EKF check msg to GCS

remove "compass" from the error message because the failure can also be
caused by GPS glitches
AP_Baro: don't include I2C MS5611 on APM1 either
Plane: added STAB_PITCH_DN_CD parameter

this adds some down trim when at throttle levels below the trim
throttle in FBWA mode.

defaults to 200 centi-degrees. I may adjust based on flight tests
AntennaTracker: do an initial pressure calibration on startup
AntennaTracker: added YAW_TRIM and PITCH_TRIM
autotest: fixed tracker sim for non-onoff mode
Copter: fix baro glitch resolved message in dataflash

Caught by Julien Dubois, thanks!
Copter: rate IMAX increase to 1000