Check for orphaned users & groups

[morgant]

Solène Rapenne recently published a blog post regarding the shell script she wrote and uses on OpenBSD to check for users & groups created by an installed package which has since been uninstalled, orphaning the user/group:

https://dataswamp.org/~solene/2023-04-03-openbsd-delete-old-users.html

She has no plans to package the script and has approved the inclusion of its functionality in swupdate:

https://bsd.network/@solenepercent/110156280843492332

I probably won't automatically remove orphaned users/groups, but note & instruct users.

[morgant]

Someone mentioned on mastodon that sysclean now shows orphaned users & groups, so this can probably be closed as #13 will handle it. Naturally, I do need to test & confirm.

[morgant]

It does look like users & groups support was added to sysclean in v3.4 with further fixes in v3.6. I'll still test before closing this issue.