Add client-side GLX protocol support for GL_ARB_texture_compression. The
extensions are *not* currently enabled. This is for several reaons. First, the server-side does not support texture compression, so there's no advantage to supporting it (yet) on the client-side. Second, I tried testing it with an IHV's closed-source driver (that advertises GL 1.3), but their server-side driver doesn't support the protocol. That means this code is largely untested.
Showing with 398 additions and 2 deletions