AppImage for Linux Zoom client

[coquec]

Instead of having different binary packages for each supported distribution, it would be great to have an official AppImage compatible with all of them. This would solve possible problems with the current packages as, for example, the missing dependencies of the current .deb Debian package in Debian Sid.

For your reference, there's an unofficial AppImage in https://github.com/probonopd/Zoom.AppImage.

Thanks!