FlightGear - Flight Simulator FGAddon

an24b: assorted minor improvements.

* an24b-set (sim/long-description): simplify and expand.
(sim/tags/ga): delete.
(sim/aircraft-data): Save payload across sessions.
(sim/allow-toggle-cockpit): true.
(input/keyboard): override Ctrl+A, Ctrl+H and Ctrl+P keyboard bindings to
drive the autopilot.
* Nasal/fuel.nas: Add a range computer like in the Lockheed1049h; see
/consumables/fuel/*.

777: improved fuel save state

E-Flash (fictional): Add files

E-Flash (fictional): add folder

ASK13: Many updates, improve JSB FDM, optimize

Airspeed-Horsa: fix model view; syntax errors in Systems/views.xml.

Cessna337: do not pollute the property tree of remote aircraft over multiplayer.

find Models/ -name '*.xml' -exec sed -r -i 's,(<prop(erty)?>)/,\1,g' {} \;

Airspeed-Horsa: re-enable aerotow over multiplayer, by enrogue.

Douglas-Dc3: enable towing a glider over multiplayer. Minor fixes.

ASG29: Various updates and fixes, remove YASim version