Currently `buildPerlPackage` prefixes the Perl version to the package's
`pname`, which results in `nix run` not being able to work for any
packages build with it out of the box. This commit corrects that and
phases out the ability to set `name` directly, as well as refactors the
code to not require `cleanedAttrs`.
* doc: add function argument order convention
Ordering by usage is the de facto ordering given to arguments. It's
logical, and makes finding argument usage easier. Putting lib first is
common in NixOS modules, so it's reasonable to mirror this in nixpkgs
proper. Additionally, it's not a package as such, has zero dependencies,
and can be found used anywhere in a derivation.
* doc: clean up usage of lib
