FlightGear - Flight Simulator FGAddon

Model animation paths are resolved relative to the model root. For the
user's aircraft that is /, but for a multiplayer aircraft it is its
/ai/models/multiplayer[n] node, and for a submodel its
/ai/models/ballistic[n] node. Global properties such as /environment,
/sim/time and /sim/rendering do not exist under those nodes, so they
need the leading slash; the aircraft's own properties must stay
relative (see r20680).

- Cockpit wind speed/direction readouts now read /environment/wind-*
(previously read zero on remote aircraft).
- M61A1 smoke submodels now read /sim/time/elapsed-sec, so the puff
scale and fade animations run.