GL_KHR_parallel_shader_compile
http://www.opengl.org/registry/specs/KHR/parallel_shader_compile.txt
GL_KHR_parallel_shader_compile

	GL_MAX_SHADER_COMPILER_THREADS_KHR 0x91B0
	GL_COMPLETION_STATUS_KHR 0x91B1
	void glMaxShaderCompilerThreadsKHR (GLuint count)