0.13.0

New major version with layered images, new features to simplify github action custom runner and several fixes.
Special thanks to @grembo for the design and implementation of layered images

Added

• import-export: add support for layered images (#151)
• POT_TMP: add a parameter to select the folder used to create temporary files
• flavour: -f option support a full pathname (#161)
• copy-out: new command to copy file or folder out from a pot (#162)

Changed

• start: simplify startup, use jexec to run pot.cmd (#150)
• flavour: the current directory is added to the flavour search path (#161)

Fixed

• start/stop: prevent stopping non-persistent jails twice (#152)
• stop: garbage collect POSIX shared memory (#150)
• start: fix ncat failing to start due to argv handling (#167)