Docker proc bump

In the process of getting `DockerProcessor` up and running again, it was necessary to update the `omero-process` image. A couple of questions:

 * Should I rework this to be on centos?
 * Is this actually `omero-py` rather than `omero-process`? `/opt/omero/bin/omero` does work.
 * ETA for omego release :) /cc @manics