public DisposableCounter(ICounter counter, MetricClock clock, Action <DateTimeOffset> action)
     : base(clock, action)
 {
     this.counter = counter;
 }
 public DisposableMetric(MetricClock clock, Action <DateTimeOffset> action)
 {
     clock.Register(action);
     this.clock  = clock;
     this.action = action;
 }