This removes the use of the old distribution code in the plugin packages
and replaces it with containerd libraries for plugin pushes and pulls.
Additionally it uses a content store from containerd which seems like
it's compatible with the old "basicBlobStore" in the plugin package.
This is being used locally isntead of through the containerd client for
now.
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
