Add object-to-path for Color/SVG-OTF text
@Tavmjong This almost works. The resulting text is Y-axis inverted and for some reason the font-size, position and X kerning needs the font DesignUnits scaling, but the Y kerning seems to be way out on the example text H which is strange.
This is an extension to the work to enable color font support by allowing the svg data to be used directly when converting into paths.
Refactoring: The PixBuf function is split with it's SVG document portion now in its own function that can return the SVG document as a Glib::ustring.