[PATCH] Additional texture maps (specular, normal, AO)

[historic_bruno]

• Specular map - relevant now that we have specularity, this would allow marking certain parts of a texture as shiny instead of the whole material (the tip of a spear, gold flecks in a mine, the metal part of a helmet but not the leather, etc.)
• Normal / bump map - typically used to simulate higher quality lighting details on a low poly model; due to the game's default view it may have more use on terrains
• Ambient occlusion map - to simulate realistic lighting of models, such a texture could be precomputed by the engine on model load and cached for efficiency

[myconid]

Adds normal, parallax, specular and self-illumination mapping

[historic_bruno]

We should probably review #1493 and #1497 first, as more general model/renderer changes, and then myconid can factor in those changes to the above patch.

[myconid]

Go here for a new patch: http://www.wildfiregames.com/forum/index.php?showtopic=16022&st=220&gopid=242432&#entry242432