writeShellApplication does not need shellcheck docs
it takes ~1 hour to compile the dependencies of pandoc on r9 5900x
because haskell is so slow
$ nix path-info -r ".#sway" --derivation | wc -l
2357
$ nix path-info -r ".#sway" --derivation | wc -l
2055
The shellcheck source code contains a manpage, so let’s add that to
the output. For good measure, also copy the README to the doc output.
The overrideMeta thing is taking care of setting the right position,
so that `nix edit` points to this file instead of to the original
haskellPackages definition.