Retain document in SVGParser, and release when we're done.
Retain document in SVGParser, and release when we're done.

MaddTheSane/SVGKit,seltzered/SVGKit,MaddTheSane/SVGKit,seltzered/SVGKit,seltzered/SVGKit,MaddTheSane/SVGKit,seltzered/SVGKit,MaddTheSane/SVGKit,seltzered/SVGKit,seltzered/SVGKit,MaddTheSane/SVGKit