Center for Bioinformatics ZBIT, Tübingen University, Tübingen, Germany. huson@informatik.uni-tuebingen.de|Center for Bioinformatics ZBIT, Tübingen University, Tübingen, Germany. huson@informatik.uni-tuebingen.de|Center for Bioinformatics ZBIT, Tübingen University, Tübingen, Germany. huson@informatik.uni-tuebingen.de|Center for Bioinformatics ZBIT, Tübingen University, Tübingen, Germany. huson@informatik.uni-tuebingen.de|Center for Bioinformatics ZBIT, Tübingen University, Tübingen, Germany. huson@informatik.uni-tuebingen.de