Completed another round of testing on AMD's (fglrx) driver

I fixed a number of issues specific to AMD's driver - changelist notes are here. Mike should hopefully push these changes to github out tonight or tomorrow latest. (3/15: These changes are live on github - thanks Mike!)

Here's Dota2 replaying on fglrx in -interactive mode. Also, our regression test suite is now working (for the first time!) on AMD, which is pretty exciting.

The GL API callstream involved is hairy - it's kinda amazing that it works at all:

- I traced Dota2 using apitrace on an NVidia 780 to a .trace file
- I played this back on AMD's fglrx using glretrace, then intercepted its output using libvogltrace to a vogl .bin trace file
- I then play this new trace using voglreplay. The regression test suite verifies that the backbuffer CRC's seen during tracing vs. replaying are the same (we've failed if not).

So we're mixing two different drivers and tracing/replaying frameworks in this test. The yellow warnings in the screenshot below are caused by missing uniforms, which are optimized differently by the AMD driver's compiler vs. NVidia (so some program uniforms are missing on AMD, which should be harmless).