first try of primitive restart index generator

Convert all quads+triangles into trangle_strip and uses primitive restart to split them.
Speed up triangle_strip, but slows down all others primitive formats.
Only implemented in ogl.

Source/Core/VideoCommon/Src/VideoConfig.h

@@ -153,6 +153,7 @@ struct VideoConfig
 		bool bSupportsDualSourceBlend; // only supported by D3D11 and OpenGL
 		bool bSupportsFormatReinterpretation;
 		bool bSupportsPixelLighting;
+		bool bSupportsPrimitiveRestart;
 
 		bool bSupportsGLSLUBO; // needed by pixelShaderGen, so must stay in videoCommon
 	} backend_info;