- implem with asyncio for steppers to simplify implementation
- with cli just run asyncio.run(main())
- with gui, run gtk in a thread and asyncio.run in main thread (or the
  reverse) and make them communicate with a queue.
- if not easily working, use https://blogs.gnome.org/jamesh/2019/08/05/glib-integration-for-python-asyncio/

Whishlist cat
=============
- gamechest update <game>, update the game if installed
- gamechest update, update all installed games
- gamechest install --all, install all available games
- gamechest remove --all, remove all available games
- gamechest install a b c, install all these games