A new flag Prs3d_Drawer::FaceBoundaryUpperContinuity() has been introduced
handled by StdPrs_ShadedShape::FillFaceBoundaries() method to exclude edges
of higher continuity class (e.g. to skip seam edges).
Draw Harness command vshowfaceboundary has been replaced by vaspects:
> vaspects -setFaceBoundaryDraw 1 -setFaceBoundaryColor RED -setFaceBoundaryType DASH.