Support SemVer for System Version

[siegenthalerroger]

We are trialing Mongock at our company and are running in to a few pain points surrounding the ordering of ChangeUnits.

We would like to be able to use a Semantic Versioning for our system version. This isn't possible currently, as the comparator used by Mongock is "alphabetical" and doesn't do the ordering as we'd expect. This leads to us having to pad the version numbers to ensure correct ordering.

• What we'd like: 22.0 / 22.0.3
• What we have to do: 0022-000

Our idea would be to support a "semver" Comparator or even better allow the setting of custom Comparators.