suggestion to add metadata describing container

[mkuzak]

BioContainers require metadata description of the container: https://github.com/BioContainers/specs/blob/master/container-specs.md
It is a good idea to do it for non-BioContainers containers too. Why should we suggest this?

[orchid00]

@mkuzak is this good for metadata in non-Biocontainers?
https://docs.docker.com/config/labels-custom-metadata/