STANBOL-1142: applied the patch provided by Sebastian Schaffert. Also changed TopicClassifier#getChainNames() to no longer throw an ChainException. Implementation should just silently ignore Chains that cause an exception.

git-svn-id: https://svn.apache.org/repos/asf/stanbol/trunk@1518628 13f79535-47bb-0310-9956-ffa450edef68