[clreq] Pull Request: Rewrite compression rules for punctuations

xfq has just submitted a new pull request for https://github.com/w3c/clreq:

== Rewrite compression rules for punctuations ==
Fix #221.

For review, but not for merge yet, because there is still a lot of room for improvement/adjustment (no pun intended).

See https://github.com/w3c/clreq/pull/307