SOLR-6550: Provide simple mechanism for passing additional metadata / context about a server-side SolrException back to the client-side

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1627154 13f79535-47bb-0310-9956-ffa450edef68
LUCENE-5974: Add check that backcompat indexes use default codecs

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1627158 13f79535-47bb-0310-9956-ffa450edef68