Markdown footnotes are not wrapped correctly

[zandaleph]

Currently, an overlong footnote like so:

[^1]: I have a funny story about this that I am not quite prepared to tell at the moment but want to tell someday.

is not rewrapped, violating an 80 character limit. Manually rewrapping to

[^1]: I have a funny story about this that I am not quite prepared to tell at
  the moment but want to tell someday.

which follows guidelines for long footnotes, is incorrectly rewrapped to

[^1]:

  I have a funny story about this that I am not quite prepared to tell at
  the moment but want to tell someday.

which is rendered as an empty footnotes and places an unwanted paragraph in the main text.

I would be able to work around this bug by simply allowing long-lined footnotes if I only had simple footnotes, but unfortunately more complicated footnotes, like this one from the footnote documentation above, are always mangled by rewrap.

[^bignote]: Here's one with multiple paragraphs and code.

    Indent paragraphs to include them in the footnote.

    `{ my code }`

    Add as many paragraphs as you like.

Would it be possible to add support for long footnotes and fix this bug? Thank you.

[rossmacarthur]

Problem the same as #63

[stkb]

Closing as duplicate of #63. I did try to fix it but found I basically had to rewrite the markdown parser to fix that (and other) bugs, which is still a WIP