Display release notes of extensions in the extension manager

The need is to be able to push some important information to the administrator of the wiki for an extension or a version of that extension.

For example, if there is an extension that has an important / breaking change in a given version, an administrator of a wiki may just see that this new version exists and upgrade towards it without going to extensions.xwiki.org to check the release notes to know that there is this breaking change.
It would be interesting for the publisher of the extension to have a way to write some information on extensions.xwiki.org (or elsewhere) about the new version and that this information is pushed to the admin of the wiki when they make the upgrade on the wiki.