[Nix-dev] Real documentation, aka "Let's kill the wiki"

[Jan Malakhovski]

I'm in support of killing wiki and writing docs in anything except
docbook.

As a side note, just want to mention that it seems to me that a lot of
people go for google/duckduckgo/whatever when searching stuff, where as
we have at least `man -k` and `man -K`, `info -k` (e.g. try `info -k
'$!'` and then `info --index-search='$!' bash`, yep, this is not ideal,
but kinda ok with an alias), `nixos-help`, and local `haddock` and
`hoogle` databases.

That is, I'd like

* All the docs to be available and discoverable locally.
  /run/current-system/sw/share/doc FTW. (easy to do)

* To have a thing that indexes all the man, info and haddock pages for
  full text search using e.g. Xapian lib. (I don't know a good tool for
  this, I'd like to get suggestions.) This can become a killer feature,
  think universal `help` command that works faster than google (local
  Xapian is extremely fast, as witnessed by `notmuch` and `mu`), that
  gives matches relevant to your system, and doesn't leak your interests
  for all the Internet to mine.

* NixOS documentation to be available in `info` format since `info` has
  index support, indexes are awesome, and navigation in `info` is kind
  of cool too (especially compared to plain HTML). (Should be possible
  with docbook2x-texi)

  Actually, if one were to extract 240KB `info` binary from 10MB
  `texinfo` package it would, in my view, become be preferable to 1.4MB
  `w3m` binary from 3.6MB `w3m` package currently used to display the
  manual in installation images. Just saying.

Cheers,
  Jan