HBASE-9243. Add more useful statistics in the HFile tool (Alexandre Normand)

git-svn-id: https://svn.apache.org/repos/asf/hbase/branches/0.94@1515553 13f79535-47bb-0310-9956-ffa450edef68
HBASE-9266 Javadoc: Document that HBaseAdmin.flush(...) is synchronous

git-svn-id: https://svn.apache.org/repos/asf/hbase/branches/0.94@1515676 13f79535-47bb-0310-9956-ffa450edef68