Textures aren't handled for 3D models

[khedoros]

Some 3D model objects (the ones embedded in uw[2].exe) are supposed to be drawn with textures.

• Texture numbers to use will be stored in the object info node, but I need to compare a few examples to figure out which numbers represent the textures

• Models may have some textured faces and some untextured faces, and I need an easy way to differentiate them, hopefully without splitting the models into 2 draw operations

• UV coordinates supplied by the game could need tweaking

• I think that some of the textures may be non-square, so I need to see if I need to enforce squareness in my image loader, if SFML already handles that for me, etc.

One big benefit here: replacing all the TMAP objects with their correct images. Stuff like the stairs up+down.

[khedoros]

This is mostly handled now. I think that the mapping may actually be reversed from the intended direction (maybe I loaded the textures backwards?) Models with variable-height vertices also need to be handled appropriately. Textures are currently annoyingly stretched; they need to be repeated and/or truncated instead.