Allow to render to SVG/image

[jonnor]

For getting a snapshot of a graph, and maybe sharing it outside the app that uses the-graph.
Could be used as basis for simple visual diffing tools for FBP graphs.

[jonnor]

I had hoped we could just use DOM-level rendering for this. I did a test with dom-to-image, which was not successful: fails with some unspecified image error event when used on the-graph-editor. However, it worked fine for some <textarea> elements etc. https://github.com/flowbased/flowtrace/commits/visualdiff

Still to be tested are some of the SVG-aware DOM node rendering methods.

[forresto]

To start, do we want to viz JSON or FBP diffs? Both? If FBP I guess we need the autolayout step.

Have you tried to mount the-graph in Phantom to get a PNG?

Github doesn't support SVG upload, so even if we can output the SVG string diffbot will need to convert it.

[jonnor]

Both ideally. We should probably run autolayout if explicit position information on nodes (x,y) is missing.

[jonnor]

Not merged yet