Merge pull request #12 from pentop/master

Histogram metric now exposes SampleMin, SampleMax, SampleCount & SampleMean
v1.0.8; additional features by @pentop (LimitedTimeSample, improvements to Histogram)
More .NETish way of emulating AtomicLong
Use UTC time instead of local time in order to make the code resilient to Daylight Saving Time changes.
Merge pull request #13 from robertmircea/master

Make AtomicLong more atomic & use UTC time for robustness