public static ExecutorServiceCloser of(ExecutorService executorService){
  return new ExecutorServiceCloser(executorService,Optional.empty());
}

public static ExecutorServiceCloser of ( ExecutorService executorService ) { return new ExecutorServiceCloser ( executorService , Optional . empty ( ) ) ; }
create an executorservicecloser for the supplied executorservice . this closer will not have an associated timeout .
