See: https://github.com/wimg/PHPCompatibility/milestone/24

Changelog:

• Add detailed changelog for version 9.0.0. Includes entry for - as of yet unmerged - PR Updated authors in composer.json #739.

Readme:

• Replace section about upgrading to v 8.0.0 with section about upgrading to v 9.0.0.
• Remove link to @wimg's blog as the information on it is out of date.
• Add information about the polyfill based rulesets.

Contributing:

• Adjust the information about specific sub-rulesets to cover the polyfill based rulesets.
• Mention the unit test @group annotations.

Other:

• .gitattributes: export-ignore the git files.
• .gitignore: add the new PHPCS 3.1+ local override file.
• composer.json: minor textual improvement to the project description.

To Do for releasing this version:

• Add info on all changes merged into master since the previous release
• Add release date - tentatively set at Sunday October 7th
• Remove unused bullets/sections
• If necessary, rebase & squash commits in this PR & merge
• Tag the release
• If any open PRs which were milestoned for 9.0.0 will not make it into the release, update their milestone.
• Close the milestone for this version
• Open a new milestone for the next version - 9.x Next has been opened.
• Tweet about the release and where relevant, mention it in Slack channels etc.

To Do after release:

• Restart the builds for the open PRs to fill the PasswordCompat and Paragonie polyfill repos.
• Once the builds have passed, merge those PRs and tag the releases.
• Add these repos to Packagist. (can't be done until there is a composer.json file in the repo).
• Restart the builds for the open PR to fill the Symfony polyfill repo and to update the WP ruleset repo.
• Once the builds have passed, merge those PRs and tag the releases.
• Add the Symfony repo to Packagist.
• Restart the builds for the open PR to update the Joomla ruleset.
• Once the builds have passed, merge the PR and tag the release.
• Restart the builds for the open PR to update the All repo.
• Once the builds have passed, merge the PR and tag the release.
• Open issues in the repos for the various polyfills to inform the repo owners and watchers of the availability of these rulesets.

[ci skip]