This produces a small luthersystems/buildpack docker image artifact which is
intended to be used as an init container for a fabric peer pod running on
Kubernetes. The init container and peer container should share an emptyDir
volume. A directory on that volume should be supplied as the single argument to
the init container and as the location of the external buildpack in the peer
core.yaml config. The init container will copy the buildpack scripts into
that directory on boot.