HBASE-8664 Small fix ups for memory size outputs in UI

git-svn-id: https://svn.apache.org/repos/asf/hbase/branches/0.95@1491903 13f79535-47bb-0310-9956-ffa450edef68
HBASE-8344. Improves the assignment when node failures happen to choose the secondary RS as the new primary RS

git-svn-id: https://svn.apache.org/repos/asf/hbase/branches/0.95@1491996 13f79535-47bb-0310-9956-ffa450edef68
HBASE-8700 IntegrationTestBigLinkedList can fail due to random number collision

git-svn-id: https://svn.apache.org/repos/asf/hbase/branches/0.95@1492035 13f79535-47bb-0310-9956-ffa450edef68