SH-2700 Fix for random black textures due to texture index out of bounds.  Also change shader to show bright pink on index out of bounds and add assertions to help prevent this sort of bug in the future.

SH-1619 FIX
SH-1620 FIX
SH-2621 FIX

* Got lighting, shadows, and ambient occlusion working on ATI macs.
* Re-enabled ambient occlusion on ATI macs.
* Re-enabled depth of field on ATI macs.

Reviewed by Runitai Linden.

SH-2675 Fix for shadow appearing on terrain at midday when terrain is totally flat and there are no prims visible

SH-1865 FIX -- removed some old non-deferred rendering code that was preventing anti-aliasing from working when GL_ARB_texture_multisample is unsupported

SH-1865 PROGRESS -- Disable the anti-aliasing control on hardware our code doesn't support for anti-aliasing

SH-2563 FIX -- Added diffuse map to the avatar rigid pass to properly set up the eyeball texture for Mac OS Lion

SH-2591 WIP -- fix for UI disappearing, introduces some artifacts in rotation ring, committing to debug elsewhere

SH-2240 Make alpha mask cutoff a little less aggressive (err on the side of not creating an alpha mask)

SH-2620 -- Enabled FXAA on OSX, which fixes the issue with latest code and some assorted shader cleanup from changeset e156c46db1b2

SH-24114 Remove unused vectorization code (outdated/unused with SSE2 requirement and llvetor4a et al)

SH-2652 Fix for black bands in high-res normal maps (break normal map generation up into tiles to handle the case where a normal map is higher resolution than the current window)