SVGUtil: fix axis rendering of multibarchart for exporting to SVG.

Exporting to SVG doesn't export the CSS properties.
Surely there is a way to include the CSS with the export, but
it is not obvious. It's easier to fix the few rendering issues
in the exported SVG by manually setting each property that fails
to export.
AnalyzeArbor: better rendering, and complete export of all SVG charts.