CONTRIBUTING.md -> Weekly Status Meetings is outdated

[bobsbeenjamin]

The weekly-status-meetings section of CONTRIBUTING.md seems to be outdated. All 3 links lead to stale resources. See the screenshot below. Also, I'm guessing the forum-and-irc section is outdated, but that's harder to tell for an outsider. Note: I was just browsing this repo, and was interested in learning more, which is how I stumbled on this.

[mgol]

PR: #541