Work Continues On FP64 Support For OpenGL 4.0 On Intel's Driver

While the RadeonSI and Nouveau NVC0 Gallium3D drivers are now at OpenGL 4.1 compliance, the open-source Intel Mesa driver remains stuck at OpenGL 3.3. Blocking the Intel driver from OpenGL 4.0 compliance is FP64 and tessellation shader sub-routine. While work is underway on both extensions -- plus ARB_vertex_attrib_64bit for OpenGL 4.1 -- it looks like the FP64 support may not be too far out...