Updated glext with latest from Khronos.
OSX: Removed dependency on SDL2.
Fixed fmin/fmax CRT library name collision.
Merge branch 'master' of github.com:bkaradzic/bgfx
Cleanup.
OSX: Moved NSOpenGLContext creation to the main thread that created NSWindow. Fixes occasional GL_INVALID_FRAME_BUFFER_OPERATION error on DrawElements.
Merge branch 'master' of github.com:bkaradzic/bgfx
Supressing clang compiler warning.