Add semver utils, using semver library

[dazza-codes]

• boolean check for a sem-ver string
• filter and sort a sequence of sem-ver strings
  • these utils are used to filter and sort a list of git tags in a subsequent PR

The focus of this PR is only on sem-ver support and not full PEP-0440 support, see:

• https://legacy.python.org/dev/peps/pep-0440/#semantic-versioning

Semantic versions containing a hyphen (pre-releases - clause 10) or a plus sign (builds - clause 11) are not compatible with this PEP and are not permitted in the public version field.

This implies that using parse_single_contraint and the poetry Version implementations may not be compatible with the intention of supporting sem-ver (assuming poetry aims only to support PEP-0440, although the poetry philosophy seems to be not to impose a specific versioning strategy on the user). This PR is focused on sem-ver support (given that full sem-ver support is not 100% compatible with PEP-0440). The responsibility for sem-ver parsing belongs with the semver dependency, to avoid recreating that wheel.

checklist

• Added tests for changed code.
• Updated documentation for changed code
  • no API docs required for this, AFAIK

[stale]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[dazza-codes]

I'm kinda giving up on contributing to poetry

• the review and merge cycle takes too long
• the project doesn't appear to be open to easy modifications or even simple refactoring

[github-actions]

This pull request has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.