Fix OpenGL3 core profile support

GL_LUMINANCE_ALPHA is not present when using a core profile
Remove support for deferred rendering

Existing support is broken in various ways and performs worse than forward rendering
call R_SyncRenderThread in RE_UploadCinematic
Call SetRequiredVertexPointers after setting the color modulate uniform
Fix for use with libgeoip < 1.5.1.
Console scrolling fixes.
‘Fix’ FXAA on Mesa (Intel, GLSL 1.2).
Fix compilation with OPENAL disabled
Enable OpenAL support by default

This was accidentally changed in commit 3ce044a
Keep main/scripts/medistat.shader up to date with release.
Send the cmd data to the backend thread instead of the struct

The code expects a pointer to the cmd data, not the struct that contains it
Fix potential GLimp_SetCurrentContext race condition
Revert "Fix potential GLimp_SetCurrentContext race condition"

This reverts commit 976025fadc63e1756bb46b3de9235692a3a67189.
Fix -Wreorder warnings
Fix most compiler warnings in the GL3 renderer
Fix many warnings in the game module
Fix warnings in client and server
Removed unused function from vanilla renderer
Remove -DUSE_GLSL_OPTIMIZER from Visual Studio cmake arguments
Move Opus from client to it's own CMake target