* for r2dock-empowered nodes monitornodes reports 3 more fields for nodes that are ssh-reachable docker_version, container_running, and container_image
4.0.9
* bugfix, better handling of unreadable images
4.0.8
* default ssh_timeout is now 2s; nodes sometimes need more time to answer about their versions and all the material requested by the monitor
4.0.7
* no longer specify a protocol when creating a SSLContext object for connecting to a plcapi endpoint, useful when plcapi runs on f33/python3.9
4.0.6
* remove asyncssh INFO messages in rhubarbe wait
4.0.5
* bugfix in monitor nodes, monitor was hanging on nodes that got killed at the wrong time