HBASE-10420 Replace KV.getBuffer with KV.get{Row|Family|Qualifier|Value|Tags}Array.

git-svn-id: https://svn.apache.org/repos/asf/hbase/trunk@1561410 13f79535-47bb-0310-9956-ffa450edef68
Add note about not permanent state in zk

git-svn-id: https://svn.apache.org/repos/asf/hbase/trunk@1561411 13f79535-47bb-0310-9956-ffa450edef68