SOLR-6641: SystemInfoHandler should include the zkHost the node is using (when running in solrcloud mode)

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1633621 13f79535-47bb-0310-9956-ffa450edef68
LUCENE-5441: Decouple (Sparse)FixedBitSet from DocIdSet.


git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1633628 13f79535-47bb-0310-9956-ffa450edef68