HBASE-5175 Add DoubleColumnInterpreter (Julian Wissmann)



git-svn-id: https://svn.apache.org/repos/asf/hbase/trunk@1581200 13f79535-47bb-0310-9956-ffa450edef68
HBASE-10821 Make ColumnInterpreter#getValue() abstract



git-svn-id: https://svn.apache.org/repos/asf/hbase/trunk@1581217 13f79535-47bb-0310-9956-ffa450edef68