Add hbasecon2013 notice

git-svn-id: https://svn.apache.org/repos/asf/hbase/trunk@1448843 13f79535-47bb-0310-9956-ffa450edef68
HBASE-7305. ZK based Read/Write locks for table operations

git-svn-id: https://svn.apache.org/repos/asf/hbase/trunk@1448867 13f79535-47bb-0310-9956-ffa450edef68