HBASE-10263 make LruBlockCache single/multi/in-memory ratio user-configurable and provide preemptive mode for in-memory type block (Feng Honghua)

git-svn-id: https://svn.apache.org/repos/asf/hbase/trunk@1556703 13f79535-47bb-0310-9956-ffa450edef68
HBASE-10301 TestAssignmentManagerOnCluster#testOpenCloseRacing fails intermittently



git-svn-id: https://svn.apache.org/repos/asf/hbase/trunk@1556708 13f79535-47bb-0310-9956-ffa450edef68