Phoenix 180

First revision for review.  There are some open points here.  Still no test case added to consume the stats.  Will do the performance test once the system is available with me.
That's right. It is the best way to do it. One more thing is inorder to retrive the latest time when the stats got updated so that based on that we don issue concurrent update stats query, should we do that in MetaDataClient with a select query or should be a normal get from the HTable? As a measure of good practice am asking this.