Change the helper script to be more generic so that transfers can go in either direction.
Change the helper script to be more generic so that transfers can go in
either direction.

No change of behavior, just a rename of variables to make it clear that
the underlying `cp` works either way.

Added default value for MANIFEST_FILE.

panoptes/POCS,panoptes/POCS,panoptes/POCS,panoptes/POCS