- Automated running kselftests
- Added README.md
- Added `net-tools' to be installed on VMs
- Added `ninja-back/virtctl.xsh' - a xonsh rewrite of the
  `src/virt-machine.sh'. Migration in `jinja/build.ninja' halfway done.
- Moved compound rules to external scripts.
- Added `ninja-back/testctl.xsh' for running test in a way that's immune
  to VM hanging or crashing.
- Updated docs for `ninja.sh'