Add a “Recent Releases” Feed

[theory]

It can just parse dist.json and turn it into an Atom feed. Might be better to do this in PGXN::API; I'm undecided.

[theory]

In the meantime, there is the twitter feed, which has releases recorded as well as links to blog posts and the occasional news-only tweet.

[theory]

Better yet, convert dist.json to JSON Feed.