Pycalver

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

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

- Fix: Use pattern from config instead of hardcoded {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: Coloured output for bump --dry

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

- Added: Support for globs in file patterns.
- Fixed: Better error reporting for invalid config.