Pycalver

- Added: Support for many more custom version patterns.

- Fixed: Better handling of pattern replacements with "-final" releases.

- Fixed github2. `pycalver init` was broken.
- Fixed pattern escaping issues.
- Added lots more tests for cli.
- Cleaned up documentation.

- Add version tags using git/hg.
- Use git/hg tags as SSOT for most recent version.
- Start using https://gitlab.com/mbarkhau/bootstrapit
- Move to https://gitlab.com/mbarkhau/pycalver

- Initial release