this removes the duplicate code. Throttle trim is not changed.

The nudge value depended on RC3_TRIM, which is not a reliable
value. It tried to only take effect when the throttle stick was above
50%, but if RC3_TRIM was high for some reason (say 1500) then it would
actually depress the throttle by a large amount, which could cause the
plane to stall.

This also adds a boolean option THROTTLE_NUDGE to allow disabling of
throttle nudging

it is perfectly valid to configure two RC channels with the same
function, especially when that function is manual output (ie. copy
input to output)

This removes the g_rc_function[] indirection array

useful for testing non-auto gps detection

this applies the wind constraint

this allows APM to cope better with airspeed sensor failure, but
ensuring airspeed stays within AHRS_WIND_MAX of ground speed

this combines with the OBC failsafe module

this sets a pin for flight termination

when enabled, this uses only the rudder to steer during takeoff and
landing, using aileron only for levelling

this allows you to disable crosstrack correction on short legs

very useful for packet forwarding setups

this fixes a seq number problem with SIMSTATE packets

this gives us a much less noisy magnetometer

With this change we average over 100 mag readings per compass.read()
call, which means we are reading the compass at over 1kHz instead of
10Hz. The noise reduction is huge.

this allows us to accumulate mag readings using spare CPU cycles

issue 733

Fix ac crosstrack display
tweak ap_mount
speed up Terminal

ArduCopter: fixes to allow AP_Mount to work on APM1 with original default channels and fix to reenable support for 3-axis gimbals on APM2.

Channels 5 to 11 changed to RC_Channel_aux.
Removed channel 9 because APM_RC doesn't support it in any case.
Updated EEPROM format version to 119 because of the change to RC_Channel_aux and because k_param_rc_11 moved to be after k_param_rc_10.

RC_Channel_aux: bug fix which could cause channel to be assigned to the wrong function and miss others

add useritems to HUD
change hdop scale
fix posible follow me bug (, vs .)
fix posible friendly params bug (, vs .)
tweak flightdata log playback timming
fix gridv2 bug. if no waypoint had been done, the grid wold fail
tweak some mission upload potential issues
add ability to get param list from a log (from startup)
add ability to get the first wp list in a log, if wps where received in that log.
tweak video capture library timing