This allows to have shorter and more future-proof IDs. This also
guarantees the IDs will only use reasonable ASCII characters (no
spaces), removing the need to encode them for PING/PONG tokens.
git-svn-id: file:///srv/svn/repo/suika/trunk@488 f0ae65fe-ee39-954e-97ec-027ff2717ef4
Uses an in-memory ring buffer.
Closes: https://todo.sr.ht/~emersion/soju/96
git-svn-id: file:///srv/svn/repo/suika/trunk@442 f0ae65fe-ee39-954e-97ec-027ff2717ef4