q2 temp entity tweaks. still more work to be done.
support sRGB (mostly)properly in gl+vk+d3d9+d3d11.
vulkan tweaks - multisample works under certain conditions. additional other changes to comply... cvars to enable some other device extensions.
removed r_viewleaf. now using clusters for q1 too.
improved compat with quakespasm's sky command.
Added vid_winthread cvar, to handle window messages on a separate thread. When set this allows the game to keep redrawing when the user is resizing the window etc.
Finally added renderers option to menusys.
git-svn-id: https://svn.code.sf.net/p/fteqw/code/trunk@5130 fc73d0e0-1445-4013-8a0c-d673dee63da5
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