Docker image digest

[sbriskin]

Please add the docker image digest in the information section.

Right now I have to use various commands to get this information:

• docker inspect --format='{{index .RepoDigests 0}}' <DOCKER_IMAGE>
• docker manifest inspect --verbose <DOCKER_IMAGE> | jq .Descriptor.digest
• skopeo inspect <DOCKER_IMAGE> | jq .Digest

But it's good to have all the information in one place.