OAK-735 - merged former way of initialing ESS with the DOSP, added SolrServerConfiguration and factored out defaults, added a unified OSGi service SolrServerProvider for OakSolrConfigurationProvider

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1464953 13f79535-47bb-0310-9956-ffa450edef68