Added "Planecrash" map, to test the crashing airplane with all its SFX.
Because the plane physically needs a lot of space, it had to be its separate map.
(plus it takes kinda long to load it all cause it has so many other required surrounding map assets)

updated lighting.
had to recompile because some signs used textures that are now lower res.

Added crashing helicopter.
Added Tugboat skybox and second model, to make sure they align.
Added the default c2m5 chopper to the c2m3 skybox version to make sure they align.
Added lights to c2m5 chopper and armored van.
Added buttons to make Clip brushes visible, because maps don't use collisionmeshes, they use clips.
Added signs to some models to tell you what mdl they are

Added APC
Added "Bunny" Helicopter
Added River_Helicoptor (yes, really)
swapped bridge with general helper props.