Optionally add back privileged extraction which can be enabled with
LUET_PRIVILEGED_EXTRACT=true
Signed-off-by: Ettore Di Giacinto <mudler@sabayon.org>
Contact the notary server if ```--verify``` is specified (or `verify:
true` is enabled on the repo config) and verify if the image is signed,
use the returned value to pull the verified image.
Create a util sub cmd to add all utils that are handy for development
and already present in the luet codebase. We expose in this case `luet
util unpack` to unpack a docker image without a docker daemon running.
