Auto downloader of Nvidia NGC containers to local mirror.
Using predefined list of container urls combined with a "skip list" of old version tags that we do not want to download/mirror.
The container repos and tags are obtained from the skopeo program (https://github.com/containers/skopeo)
and the containers are pulled to disk using singularity, producing production ready singularity images.
The local file structure is a direct mirror of the package repository structure, and is used here to detect already downloaded container tags. I.e. re-running this script will only download new container tags not currently present on local disk.
Author: Hugo U.R. Strand (2020)