Implement "shutdown" werb for services
    
    This patch does not implement a dummy "shutdown" for non-service
    daemons, in line with the original proposal by Attila. Also, it
    does not wait for stopping (since you're going to wait for a long
    time anyway in case of feral processes -- see the bz for recommended
    practices).
    
    Resolves: rhbz#927423