Allow using Octochangelog as an alternative changelog generator

[kayw-geek]

This tool is fantastic! I'm currently using it in my automated package upgrade workflow to generate PR descriptions.

Recently, I discovered a clearer and more intuitive version comparison tool called Octochangelog. I'm wondering if we could introduce an optional parameter or some configuration option to allow users to choose Octochangelog as their changelog generator.

If you think this is a good idea, I'd be happy to submit a PR to implement this feature. Let me know your thoughts!