SOLR-5853: Return status for AbstractFullDistribZkTestBase#createCollection() and friends

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1577156 13f79535-47bb-0310-9956-ffa450edef68
SOLR-5783: fix mixing caching + non caching searchers, fix multiple registration of same searcher

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1577167 13f79535-47bb-0310-9956-ffa450edef68
SOLR-5861: Recovery should not set onlyIfLeaderActive=true for slice in 'recovery' state

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1577228 13f79535-47bb-0310-9956-ffa450edef68