Suggestion: X number of releases

[AlecRust]

Thanks for this great package!

I'm using auto-changelog in GitHub Actions to generate changelog in a WordPress plugin readme.txt using a Handlebars template.

As-per WordPress guidelines I don't want to include every release in this changelog, I only want to include say the last 5 releases.

Within the context of GitHub Actions it's difficult to pass something like --starting-version ${5 tags ago} or --starting-date ${2 months ago from today}.

Have you considered supporting a "last X releases" option? Then I could pass something as simple as --releases-ago 5.

[IllusionVK]

This is also very important for us as https://appcentre.ms limit the length of change logs for a release to 5000 characters, so we need to limit to show the last 1-2 versions in the change log with each version we push. We use --starting-date now, but we need to manually change the date every time as we could not identify an easier way to do this. Also thanks for the great package!