 Aircraft; Smoke animation when damaged

Aircraft Smoke


When aircraft creates a smoke trail because of heavy damage, the animation used
is hardcoded and the same for all AircraftTypes, yet it is looked up
each time anew for every aircraft anyhow. When an aircraft is destroyed, it
creates lots of smoke animations. This fix gets rid of the superfluous lookup.
Additionally, the smoke has been made customizable per AircraftType.

[AircraftType]Smoke.Anim=animation
  The animation created as smoke trailer. Defaults to SGRYSMK1.

[AircraftType]Smoke.ChanceRed=integer - percent
  The chance of a heavily damaged aircraft creating a smoke animation each
  frame. Defaults to 10.

[AircraftType]Smoke.ChanceDead=integer - percent
  The chance of a crashing aircraft creating a smoke animation each frame.
  Defaults to 80.

 0.7
