CI: Revise code that deals with NUT versions to compare them numerically component-by-component #3055
Description
...scripts expecting more or less alphanumeric comparisons (so single-digit version components) do not help either...
Originally posted by @jimklimov in #3053
Cover shell, perl, python, sed/grep/awk, POSIX make, maybe more. Check also nut-website.
This is more or less a required prerequisite for conversion to "MAJOR.MINOR" releases aligned with standard SEMVER usage, with ".PATCH" part left for hot-fixes over existing releases (so eventually moving away from "release is a snapshot of master, stale and obsolete after the next commit lands" stance).
Note that NUT SEMVER deals with up to 5 dot-separated numeric components (and then some suffix parts), see https://networkupstools.org/docs/developer-guide.chunked/versioning.html for more details.