SITL: FlightAxis Improvements

[robertlong13]

Adds a new options parameter for the FlightAxis SITL frame:

• Option to automatically reset the aircraft position in RealFlight!!
• Move the existing framestring-passed options to option bits (but keep the existing framestring parsing for now)
• Option to silence the FPS reporting printf

[tridge]

good to merge after these changes

[timtuxworth]

It makes sense to not call it FlightAxis - RealFlight stopped calling it that in (I think) Evolution.

[robertlong13]

It makes sense to not call it FlightAxis - RealFlight stopped calling it that in (I think) Evolution.

Agreed. It's an unfortunate historical holdover that we should fix in a future PR. That said, the param name we should go ahead and set correctly now.

[robustini]

@robertlong13 sorry to comment here that a merge has already been done, but since even before the 4.5.7 release I have been noticing problems with Flightaxis and Realflight.
Never seen this behavior before: moving RC4 with the joystick I also have a shift of about 100 uS up and down of CH8.
Having assigned CH8 to the flight modes so moving the directional also changes my flight modes, and it is not nice.
Obviously on the controller panel of Realflight this thing by moving that channel does not happen, so I think it is attributable to flight axis.
No active mixing in TX, in fact in Realflight without Flighaxis the rudder CH4 channel does not interfere with the one on CH8.

[robertlong13]

@robustini, it's extremely unlikely that this has anything to do with this PR, but I can probably help. We should take this conversation to Discord though.