SH-2243 work in progress -- don't use gl_FragColor or gl_FragData for outputs -- no more deprecation warnings on nvidia

SH-2242 Physics shape display works again, added asserts to flush out areas where state being consumed by a shader does not match state being provided by vertex buffers.

Reviewed by davep.

SH-2242 FXAA support instead of unreliable multisample textures (done here because it's a smaller change than integrating glVertexAttrib with FSAA pipe).  Shader integration with LLDynamicTexture subclasses.

SH-2238, SH-2223, SH-SH-2242 glVertexAttrib throughout main render pipeline complete, preview renders and debug displays still pending.  Also fixed a render glitch and a crash (JIRAs listed).

SH-2181 Fix for alpha flickering when basic shaders enabled (don't use glAlphaFunc when shaders are available).

Reviewed by Leslie

SH-1990 Fix for redundantly applying some color scaling to sky and water (also add some snazzy specular bloom from the sun)

SH-2031 High risk changeset, but potentially high reward.  Addresses frame stalls in renderer by never using the fixed function pipeline if shaders are available.

SH-1682 Dynamically adjust the number of texture channels to use for indexed texture rendering based on available hardware.

SH-469 Don't use depth buffers and multisample buffers where not absolutely needed -- make sample counts consistent between shaders and render targets.