Implemented specular reflective lighting for OpenGL 3.x, everything looks shiny (will add APIs to make it less shiny ;-)

Remove roof from kitchens/1.sdf, otherwise shadows and shinyness won't work (light is outside the room, bouncing against roof-top)
Make kuka_iiwa/model.urdf more smooth, use .obj for per-vertex normals (using Blender, import STL, export OBJ, enable triangles, normals and Z-UP, Y forward)

examples/OpenGLWindow/GLInstancingRenderer.h

@@ -124,6 +124,7 @@ public:
 	
 	virtual void setLightPosition(const float lightPos[3]);
 	virtual void setLightPosition(const double lightPos[3]);
+	void setLightSpecularIntensity(const float lightSpecularIntensity[3]);
 
 	virtual void	resize(int width, int height);
 	virtual int	getScreenWidth()