ANN: CommonMark 0.22

Version 0.22 of the CommonMark spec
has been released, as well as versions 0.22.0 of cmark, the C reference implementation
and commonmark.js, the JavaScript reference implementation.

Changelogs can be found at the links provided.

This release fixes a few minor glitches in the last release’s revision of HTML block rules, adds some test cases, and makes a few other minor improvements.