Remove `Z` and `N` (and more?) as built-ins
There doesn't seem to be fundamental reasons to include built-in support for Z and N. Those could easily be provided as a data-encoding.zarith subpackage. It would lighten the core library.
There doesn't seem to be fundamental reasons to include built-in support for Z and N. Those could easily be provided as a data-encoding.zarith subpackage. It would lighten the core library.