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

See https://wiki.lindenlab.com/wiki/License_Substitution for details.

back-out the back-out for this branch.  yay.

Backing out this merge that I pushed (prematurely) to the wrong place.

kill already-nerfed quadratic attenuation which it seems we won't be supporting any decade soon.

kill already-nerfed quadratic attenuation which it seems we won't be supporting any decade soon.

kill already-nerfed quadratic attenuation which it seems we won't be supporting any decade soon.

cheaply resurrect the difference between spotlight and omnidirectional, as far as the shader is concerned.

not complete.

cheaply resurrect the difference between spotlight and omnidirectional, as far as the shader is concerned.

not complete.

cheaply resurrect the difference between spotlight and omnidirectional, as far as the shader is concerned.

not complete.

next, needs the non-shader GL lighting model to be equally dumb (it's too smart - kill the spot angle.

next, needs the non-shader GL lighting model to be equally dumb (it's too smart - kill the spot angle.

next, needs the non-shader GL lighting model to be equally dumb (it's too smart - kill the spot angle.

QAR-389

windlight14 which have passed QA (up through r79932).

svn merge -r 80831:80833 svn+ssh://svn.lindenlab.com/svn/linden/branches/merge_windlight14_r80620