Auto-post Vue changelogs in #announcements.

[sustained]

Overview

Via the Github API, we can automatically detect new releases and post them to #announcements.

Rationale

It's hard enough work to maintain a changelog already without also having to notify people via a variety of different channels (e.g. Slack, Discord, Twitter, Facebook).

Potential Issues

None.

Additional Information

Additionally, you could even have a role e.g. release-notifications, which users can add to themselves !add-role release-notifications, and then they will be notified whenever there's a release. No doubt some users would like this.

Pull Request

#73