Group release notes items by category (features, fixes, etc).

[caarmen]

Regarding the release notes:

Thank you for highlighting the important changes in release notes in an "important" section :pray:

Would it be possible to organize the other changes, to make it easier to browse the changes?

Like: group the bug fixes together, new features together, doc changes together, lib updates together.

It would be really helpful to have an idea of the impact of upgrading to a new release.

Thanks a lot!