WIP: Bookmarklet: Open depviz for the issue you're currently viewing

[wking]

This still needs test coverage for run().

I'd like to have "The depviz bookmarklet" as the link text (and not just "depviz"), but both Chromium and Firefox use the link text as the default bookmark name. By using only "depviz", we get a sane bookmark name without the user having to edit anything when creating the bookmark.

This is made tricky by GitHub's Content Security Policy, which doesn't play nicely with all browsers. Despite the open Chromium issue, the bookmarklet does work for me with Chromium 54.0. And as expected from the open Firefox issue, the bookmarklet does not work for me on Firefox 45.4.

[jbenet]

cool!

[jbenet]

up to you when to merge