- Changelog has been moved from a specific file `CHANGES.md` to the
  reference manual; former Credits chapter of the reference manual has
  been split in two parts: a History chapter which was enriched with
  additional historical information about Coq versions 1 to 5, and a
  Changes chapter which was enriched with the content formerly in
  `CHANGES.md` and `COMPATIBILITY`
  (`#9133 <https://github.com/coq/coq/pull/9133>`_,
  `#9668 <https://github.com/coq/coq/pull/9668>`_,
  `#9939 <https://github.com/coq/coq/pull/9939>`_,
  `#9964 <https://github.com/coq/coq/pull/9964>`_,
  by Théo Zimmermann,
  with help and ideas from Emilio Jesús Gallego Arias,
  Clément Pit-Claudel, Matthieu Sozeau, and Enrico Tassi).

Add changelog entry about moving changelog to refman.
Add changelog entry about moving changelog to refman.
