SOLR-6850: AutoAddReplicas makes a call to wait to see live replicas that times  out after 30 milliseconds instead of 30 seconds.

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/branches/branch_5x@1647461 13f79535-47bb-0310-9956-ffa450edef68
SOLR-6881: Add split.key support for SPLITSHARD via SolrJ (merge from trunk)

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/branches/branch_5x@1647465 13f79535-47bb-0310-9956-ffa450edef68
SOLR-6868: Try to fix the failing test and also a part of the SolrJ collection API test refactoring (merge from trunk)

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/branches/branch_5x@1647474 13f79535-47bb-0310-9956-ffa450edef68