Second part of documentation commit. git-svn-id: https://svn.apache.org/repos/asf/hadoop/hbase/trunk@638612 13f79535-47bb-0310-9956-ffa450edef68
Part 1: Basic documentation. git-svn-id: https://svn.apache.org/repos/asf/hadoop/hbase/trunk@620246 13f79535-47bb-0310-9956-ffa450edef68