Hawk cannot run on Eclipse 2022-03 + Java 17 due to XStream issues

I have just tried to run Hawk from an Eclipse 2022-03 installation with Java 17. It fails with errors coming from XStream, which appear to be due to how some parts of Eclipse appear to be based on modules now.

This may require a change away from XStream into something more up to date: in fact, I think it may be good to start storing configuration files in something like YAML, with a more human-friendly format.