Add commit statistics to the changelog

[orhun]

Is your feature request related to a problem? Please describe.

cargo-smart-release has a cool feature that adds the commits statistics to the changelog:

Commit Statistics
7 commits contributed to the release.
83 days passed between releases.
1 commit was understood as conventional.
0 issues like '(#ID)' were seen in commit messages

Describe the solution you'd like

Implement the same functionality in git-cliff and make it configurable via template.

I'm thinking it can be accessed via {{ statistics }} variable.

Describe alternatives you've considered

None.

Additional context

See CommitStatistics struct in https://github.com/Byron/cargo-smart-release/blob/main/src/changelog/section/segment.rs

[melMass]

I tried a few tools like git-cliff before but it's by far my favorite one!
This issue is the last "critical" thing I miss from it. Mainly to be able to spot missed/ignored commits.
Thanks for the great work