[Feature Request] Extra parameter `--appimage-list`

I would like to see an extra parameter, *`"--appimage-list"`*, to be used when running an AppImage. This parameter should also be listed when running with *`"--appimage-help"`*.

It should then list all the files (with their paths and the name of the sub-directory) where the AppImage contents end up if it was run with *`"--appimage-extract"`*.