SOLR-6543: Give HttpSolrServer the ability to send PUT requests

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1627460 13f79535-47bb-0310-9956-ffa450edef68
Remove obsolete string

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1627467 13f79535-47bb-0310-9956-ffa450edef68