SOLR-5437: DeleteReplicaTest fails constantly both locally and in jenkins
SOLR-5486: Cleanup and harden DeleteInactiveReplicaTest.

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/branches/branch_4x@1544839 13f79535-47bb-0310-9956-ffa450edef68