WARNING: This is only trivially tested. There is at least one
	known crash when referencing missing templates. No data loss
	has been observed, but exercise caution.

This is a modification of Plan 9's wikifs(4) to add generation of
gemtext from the wiki entries. Most of the formatting is the
obvious conversion. Links in the wiki entry are given an anchor
in the text [like so], and all referenced links are output in
gemtext format at the end of the entry, footnote-style. It would
be preferable to have these output at the end of the section of
the wiki document in which they appear, but that has not been
done (yet?).

The index.gmi file for each entry is generated using the page.gmi
template, analogously to how index.html and index.txt are done,
from your wiki root (typically /sys/lib/wiki).

I haven't bothered to make a wiki2gmi.c, although it'd be easy.

The man page has not yet been updated.