public void AgoUTC()
        {
            using (ThreadLocalServiceLocator.Push(new FreezingClockLocator()))
            {
                var past = 10.Days().Ago(DateTimeKind.Utc);
                var now  = TimeSpanCalendarExtensions.Extensions.UtcNow;

                Assert.Equal(past, now.Subtract(TimeSpan.FromDays(10)));
                Assert.Equal(DateTimeKind.Utc, past.Kind);
            }
        }
        public void FromNowUTC()
        {
            using (ThreadLocalServiceLocator.Push(new FreezingClockLocator()))
            {
                var future = 10.Days().FromNow(DateTimeKind.Utc);
                var now    = TimeSpanCalendarExtensions.Extensions.UtcNow;

                Assert.Equal(future, now.AddDays(10));
                Assert.Equal(DateTimeKind.Utc, future.Kind);
            }
        }