code: function unlink(mode, target, system, containerDef, container, out, cb) {
      logger.info('unlinking');
      out.stdout('unlinking');
  
      var elb = findParentELB(system, container);
  
      if (elb) {
        logger.info(elb, 'elb found');
        unlinkFromELB(mode, system, elb, container, out, cb);
      } else {
        logger.info('elb not found');
        cb(null, target);
      }
    }
docs: unlink the container from the target
  target - target to deploy to
  system - the target system defintinion
  cdef - the contianer definition
  container - the container as defined in the system topology
  out - ouput stream
  cb - complete callback