[Workbench] "Download" / "Save as" button for provenance graph
A "Download" button on the provenance graph view page, to deliver just the image data, would be a pretty snazzy thing to have. As it stands, with the SVG data inlined in the HTML source, there's no image that the user can right-click on to download.
An SVG file gives the user lots of options, like touching up the graph, editing the text, and using it as a figure in a document (and is likely easier to implement), but an option to download a PNG file would be nice too.
"Save as SVG" can be done entirely in the (modern) browser: http://html5-demos.appspot.com/static/a.download.html