--appimage-extract-and-run verbosity is not configurable

[hongtron]

Currently, the --appimage-extract-and-run flag echos the extraction output to STDIN. This information is good for debugging, but is not always desired, e.g. in a frequently-used image in a Docker container. It would be helpful to be able to specify the level of output based on the use case (e.g. launching the image for use vs. debugging).