Bumpver

- Add deprication warning to README.md

- Fix: Don't use git/hg command if `commit=False` is configured (thanks valentin87)

- Fix [gitlab6][gitlab_i6]: Add parts `{month_short}`, `{dom_short}`, `{doy_short}`.
- Fix [gitlab5][gitlab_i5]: Better warning when using bump with SemVer (one of --major/--minor/--patch is required)
- Fix [gitlab4][gitlab_i4]: Make {release} part optional, so that versions generated by --release=final are parsed.

[gitlab_i6]: https://gitlab.com/mbarkhau/pycalver/-/issues/6
[gitlab_i5]: https://gitlab.com/mbarkhau/pycalver/-/issues/5
[gitlab_i4]: https://gitlab.com/mbarkhau/pycalver/-/issues/4

- Fix: Use pattern from config instead of hard-coded {pycalver} pattern.
- Fix: Better error messages for git/hg issues.
- Add: Implicit default pattern for config file.

- Fix: Add warnings when configured files are not under version control.
- Add: Colored output for bump --dry

- Fix: Allow --release=post
- Fix: Better error reporting for bad patterns
- Fix: Regex escaping issue with "?"