Consolidate credits and changelog information in a single place. #9668
This PR consolidates our credit chapter and our CHANGES file in a single place.
Following Enrico's proposal of using reverse chronological order for the recent credits, while keeping chronological order for older ones, the credits chapter is split in two parts:
The content of CHANGES (expect the unreleased version) and the historic (and archived) COMPATIBILITY file have been move into the new History and Changes chapters.
Later work includes:
@vbgl I propose to do this change in 8.10. For now, the
The plan is that the next version (8.11) will use a different mode for storing the change info, inspired by GitLab (and supported by @SkySkimmer). A branch showing what this would give is at https://github.com/Zimmi48/coq/tree/test-split-CHANGES/changelog.