public void Exponential()
        {
            IDelayStrategy strategy = new ExponentialDelayStrategy(TimeSpan.FromMilliseconds(100));

            Assert.AreEqual(TimeSpan.FromMilliseconds(100), strategy.NextDelay());
            Assert.AreEqual(TimeSpan.FromMilliseconds(200), strategy.NextDelay());
            Assert.AreEqual(TimeSpan.FromMilliseconds(400), strategy.NextDelay());
            Assert.AreEqual(TimeSpan.FromMilliseconds(800), strategy.NextDelay());
        }