Lighting

[ThomasMountainborn]

The world is currently unlit. We need to implement lighting.

• [x] Use vertex color lighting of outdoor geometry.
• [x] Add vertex normals.
• [ ] Use lightmaps for indoor geometry.
• [ ] Lightmapped lights have to affect NPCs and the player.
• [x] Diffuse light shader for sun and point lights.
• [ ] Set sun and ambient light values from the sky manager.
• [x] Create light vobs for lights and fires.
• [x] Handle many lights per mesh. (see this issue)
• [ ] Enable fire only at night.
• [ ] Animate fire.
• [ ] Optimize meshes slightly using separate vertex attribute arrays for position and everything else.
• [ ] Find missing light sources, such as the green light under the big grate in the OC castle. (probably just the lightmap though)