code: private void update_from_remote( ) {
      Job remote = DKV.getGet(_key); // Watch for changes in the DKV
      if( this==remote ) return; // Trivial!
      if( null==remote ) return; // Stay with local version
      boolean differ = false;
      if( _stop_requested != remote._stop_requested ) differ = true;
      if(_start_time!= remote._start_time) differ = true;
      if(_end_time  != remote._end_time  ) differ = true;
      if(_ex        != remote._ex        ) differ = true;
      if(_work      != remote._work      ) differ = true;
      if(_worked    != remote._worked    ) differ = true;
      if(_msg       != remote._msg       ) differ = true;
      if(_max_runtime_msecs != remote._max_runtime_msecs) differ = true;
      if(! Arrays.equals(_warns, remote._warns)) differ = true;
      if( differ )
        synchronized(this) { 
          _stop_requested = remote._stop_requested;
          _start_time= remote._start_time;
          _end_time  = remote._end_time  ;
          _ex        = remote._ex        ;
          _work      = remote._work      ;
          _worked    = remote._worked    ;
          _msg       = remote._msg       ;
          _max_runtime_msecs = remote._max_runtime_msecs;
          _warns     = remote._warns;
        }
    }
docs: Update the *this* object from a remote object.