our xslt already replaces double line breaks with a paragraph close and
reopen. not using explicit para tags lets nix-doc-munge convert more
descriptions losslessly.
only whitespace changes to generated documents, except for two
strongswan options gaining paragraph two breaks they arguably should've
had anyway.
Using pkgs.lib on the spine of module evaluation is problematic
because the pkgs argument depends on the result of module
evaluation. To prevent an infinite recursion, pkgs and some of the
modules are evaluated twice, which is inefficient. Using ‘with lib’
prevents this problem.