Those are mostly empty, and now totally irrelevant.

This breaks the automatic generation, but it's unlikely anyone would
have noticed that anyways.

It would be better if those sections were represented in the folder
hierarchy as well, but that involves moving a lot of pages around,
which would break too many links.

Ideally, the GitLab wiki would support redirects, but unfortunately it
didn't seem to, in my tests:

https://forum.gitlab.com/t/gitlab-wiki-redirections-and-other-gollum-features/42993/1

This displays better in emacs' outline mode

The wiki still claimed it has its source at https://gitweb.torproject.org/project/help/wiki.  Correct that

The $() was being interpolated by the caller, and the
pg_upgradecluster command was incomplete.