Sketcher: Constraint svg caching
Sketcher: Constraint svg caching

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Calls to:
Gui::BitmapFactory().pixmapFromSvg(type.toLatin1().data(),QSizeF(edit->constraintIconSize,edit->constraintIconSize));

are expensive and the scaled pixmap is heavily reused.

Solution is to cache the icon.

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