The reference/docker package was a fork of github.com/distribution/distribution,
which could not easily be used as a direct dependency, as it brought many other
dependencies with it.
The "reference' package has now moved to a separate repository, which means
we can replace the local fork, and use the upstream implementation again.
The new module was extracted from the distribution repository at commit:
b9b19409cf
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
4923470902