LUCENE-5376, LUCENE-5477: add near-real-time suggest updates when using AnalyzingInfixSuggester to Lucene demo server

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/branches/lucene5376@1573080 13f79535-47bb-0310-9956-ffa450edef68