[WIP] P-51 Mustang (v2.0)

Lots of things have been fixed already:
- Air intake is no longer white (now with inside)
- A thinner rudder
- 3D Exhausts (not just a texture)
- Brighter and shiny (reflection) textures
- Interior

I still have to do:
- Transparant glass
- Smaller ailerons

Here's a picture (at night).
You can see the textures are brighter, the Air Intake has been fixed and you can see the 3D Exhausts.

Oh, and I also added a new propellor :)