HBASE-7990 Backport HBASE-5837 'hbase shell deleteall to .META. allows insertion of malformed rowkey' to 0.94



git-svn-id: https://svn.apache.org/repos/asf/hbase/branches/0.94@1452443 13f79535-47bb-0310-9956-ffa450edef68
HBASE-7824 Revert until TestMasterFailover passes reliably



git-svn-id: https://svn.apache.org/repos/asf/hbase/branches/0.94@1452452 13f79535-47bb-0310-9956-ffa450edef68
HBASE-7991 Backport HBASE-6479 'HFileReaderV1 caching the same parent META block could cause server abort when splitting' to 0.94



git-svn-id: https://svn.apache.org/repos/asf/hbase/branches/0.94@1452465 13f79535-47bb-0310-9956-ffa450edef68