Fix for CONNECTORS-972.

git-svn-id: https://svn.apache.org/repos/asf/manifoldcf/trunk@1620301 13f79535-47bb-0310-9956-ffa450edef68
Improve error reporting for unhandled SolrServerExceptions

git-svn-id: https://svn.apache.org/repos/asf/manifoldcf/trunk@1620302 13f79535-47bb-0310-9956-ffa450edef68