Sozi release 22.02.23 for testers

This intermediate release aims at fixing installation issues and testing new packaging options.
It addresses the following concerns:

• Debian packages should be installable in Debian, Ubuntu and their derivatives (#572)
• Linux users will now benefit from an AppImage package (#602)
• Launching failed with an error in some Linux distributions (#603)
• RPM packages should not conflict with other Electron applications (#605)
• Windows users will be able to install Sozi using an executable installer.

These packages have been installed successfully in several operating systems (in virtual machines in some cases):

• Debian 11 "Bullseye": .AppImage, .deb
• Fedora 35: .AppImage, .rpm
• Manjaro: .AppImage, .pacman
• OpenSUSE Tumbleweed: .AppImage, .rpm (ignoring messages about missing dependency libuuid, and about signature verification).
• Ubuntu 20.04 LTS "Focal Fossa": .AppImage, .deb
• macOS 11.6.4 "Big Sur": -mac.tar.xz
• Windows 10: .exe

If you want to help me improve Sozi, please try to install one or more of these packages and report any success or issue that you encounter.