Changes

Summary

1. include ssh + rsync as required for Isabelle tools, e.g. "isabelle sync";
2. more robust: snap version of docker cannot access /tmp;
3. tuned signature;
4. update to scala-3.2.0; enforce rebuild of Isabelle/ML + Isabelle/Scala;
5. avoid crash of JLine on Windows;
6. update to jdk-17.0.4.1+1 from 22-Aug-2022 (https://docs.azul.com/core/zulu-openjdk/release-notes/11.58-17.36-august-2022);
7. clarified default, following 8b695e59db3f;
8. tuned signature;
9. tuned;
10. clarified modules;
11. discontinued pointless SSH.Target: OpenSSH client can handle user@host directly;
12. clarified options;
13. clarified options;