Draft: improve initial code of getSVG
Draft: improve initial code of getSVG

Improve also the docstrings, and minor adjustments in PEP8 style
and spacing.

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