LUCENE-5149: CommonTermsQuery should allow minNrShouldMatch for high & low freq terms

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/branches/branch_4x@1508455 13f79535-47bb-0310-9956-ffa450edef68
SOLR-5087, CoreAdminHandler.handleMergeAction generating NullPointerException. Thanks Patrick

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/branches/branch_4x@1508491 13f79535-47bb-0310-9956-ffa450edef68
Added entry for SOLR-5087

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/branches/branch_4x@1508494 13f79535-47bb-0310-9956-ffa450edef68