fixes 0003571: Offset3D of volumes intersection is not solid
fixes 0003571: Offset3D of volumes intersection is not solid

Fat-Zer/FreeCAD_sf_master,Fat-Zer/FreeCAD_sf_master,Fat-Zer/FreeCAD_sf_master,Fat-Zer/FreeCAD_sf_master,Fat-Zer/FreeCAD_sf_master