improve to 1. show stacktrace on error, 2. alert user when they don't pass the path to index rather than cryptic nullpointerexception
improve to 1. show stacktrace on error, 2. alert user when they don't pass the path to index rather than cryptic nullpointerexception

git-svn-id: 4c5078813df38efa56971a28e09a55254294f104@808190 13f79535-47bb-0310-9956-ffa450edef68

tokee/lucene,tokee/lucene,tokee/lucene,tokee/lucene