Add @Azaezel's exception for Win32

"This chunk causes issues on the win8.1/non-SDL side."

Engine/source/gfx/gl/tGL/tGL.h

@@ -24,8 +24,13 @@
 #define T_GL_H
 #include "GL/glew.h"
 
-// Slower but reliably detects extensions
+#if defined (TORQUE_OS_WIN)
+// This doesn't work on Mesa drivers.
+#define gglHasExtension(EXTENSION) GLEW_##EXTENSION
+#else
+// Slower but reliably detects extensions on Mesa.
 #define gglHasExtension(EXTENSION) glewGetExtension("GL_" # EXTENSION)
+#endif
 
 #endif