@Override
    public boolean cancel(boolean aMayInterruptIfRunning) {
      return future.cancel(aMayInterruptIfRunning);
    }
Handle control tasks. Control tasks are used by the Coordinator
to control Worker instances. For example to stop an ongoing task
or to adjust something on a worker outside the context of a job.
src/main/java/com/creactiviti/piper/core/Worker.java