Make links in footnotes create new footnotes

[doersino]

Since links in the body text are turned into footnotes of the form "See .", the same procedure (as every year) should be applied to links found within footnote contents.

Idea: Put footnote content into a display: none element right after the first reference to that footnote, then Bindery should be able to pick up any contained links? But this wouldn't put a footnote marker (for the link) into the footnote content, hmm.