This script helps restart the AFS servers, which is useful when
updating parameters. It can also enable audit logging.
It can also stop and start the servers, although it's unlikely we'd
want all the servers offline at the same time so stopping has a
warning included.
Documentation is updated to refer to the helper script
Change-Id: Idcb3e43a3f6e614cdb787d4334e692a98bffdd15