Flatpak or AppImage support

[flexxxxer]

It would be nice to not install dependencies on the system and not rely on versions from the system. this is to avoid dependency hell and simplify software delivery. I'm even willing to help, but I'm not using Linux on a regular basis yet to thoroughly test.

[digitaltrails]

I'd prefer others to create and maintain packages, either distro specific, or generic Flatpak or AppImage. For example, @yochananmarqos is kindly looking after the Arch/Manjaro AUR packaging.

I'm happy to consider changes to the source that might assist others with packaging or porting to a different distro/OS.

I don't have any Flatpak or AppImage experience. I'm not sure how Flatpak or AppImage deal with access to /dev or /sys. For example, how would they allow access to the devices used by ddcutil, such as /sys/class/drm/card0-DP-* or the feed from /dev/ttyUSB0 for the arduino based lux-metering. Because ddcutil can now be accessed via D-Bus, maybe that's how vdu_controls could be made to work with Flatpak, but that adds a dependency on the the D-Bus ddcutil-service, which would need device access, so maybe that's just moving the problem elsewhere.