ocpsvg: OCP ⟷ SVG

• works at the OCP level
• uses svgpathtools to convert SVG path strings to and from TopoDS_Edge, TopoDS_Wire, and TopoDS_Face objects
• uses svgelements to import TopoDS_Wire and TopoDS_Face objects from an SVG document
• can be used to add SVG functionality (import and export) to higher level API