HBASE-10500 Some tools OOM when BucketCache is enabled

git-svn-id: https://svn.apache.org/repos/asf/hbase/trunk@1567687 13f79535-47bb-0310-9956-ffa450edef68
HBASE-7849 Provide administrative limits around bulkloads of files into a single region

git-svn-id: https://svn.apache.org/repos/asf/hbase/trunk@1567736 13f79535-47bb-0310-9956-ffa450edef68