How to descibe more than one container
The ESCAPE template project contains two container images, one for docker and one for singularity. https://zenodo.org/record/4923992
The AMIGA-IAA/hcg-16 use case contains three container images, each containing different software. https://github.com/AMIGA-IAA/hcg-16/tree/master/docker
ESAP needs to be able to show the user what containers are available, and it needs to know what services are able to run them.