A new flag myToPropagateVisualState is introduced for PrsMgr_PresentableObject: by default it is true, it means that the visual state (display/erase/color) should be propagated to all children. If false, the visual state is not propagated.
The flag can be set via the method ToPropagateVisualState() or via Draw command: "vparent <parent> -ignoreVisu"
