Version 5 is incompatible for some icons, so projects that depend on it
need to actively convert the symbols, see:
https://github.com/greshake/i3status-rust/issues/130
Reintroducing the old version lets us use those programs that haven't
been updated.
Was removed in 0a393f53a9
* make font derivations fixed-output where applicable
* fix dead links
* `stdenv.lib` -> `lib` where `stdenv` is not involved
* remove `meta.platforms = [ unix ]` and `meta.platforms = [ linux ]` because the restriction has no sense for data packages