Refactored R_UpdateEntityLighting to CL_UpdateEntityShading, which sets fields like...

Refactored R_UpdateEntityLighting to CL_UpdateEntityShading, which sets fields like ent->render_modellight_ambient.

Added texture->render_modellight_ambient and similar fields which concretely define how the material is to be rendered, so all of the various tweaks and modifiers are no longer buried in R_SetupShader_Surface which has now been refactored heavily.

Removed R_LightPoint as it's really not necessary - this change will make lit particles a little bit slower as R_CompleteLightPoint is a slightly more expensive function.

Refactored R_CompleteLightPoint to have more consistent code, changed the final color math so that it passes q1bsp/q2bsp lighting through unmodified.

Changed shading of tag_entity attachments - they now use the root entity's origin for shading, this fixes r_shadows where the shadows could go in different directions on CSQC entities (r_shadows code already contained a hack to work around this problem for network entities).

Renamed r_refdef.lightmapintensity and ambient to r_refdef.scene.lightmapintensity and ambientintensity.

git-svn-id: svn://svn.icculus.org/twilight/trunk/darkplaces@12376 d7cf8633-e32d-0410-b094-e92efae38249
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