LUCENE-5999: Fix backcompat support for StandardTokenizer

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/branches/branch_5x@1630189 13f79535-47bb-0310-9956-ffa450edef68
SOLR-6513: Add a collectionsAPI call BALANCESLICEUNIQUE

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/branches/branch_5x@1630191 13f79535-47bb-0310-9956-ffa450edef68