replaced manual toString method with eclipse generated

vipra-util/src/main/java/de/vipra/util/model/Article.java

...a-util/src/main/java/de/vipra/util/model/ArticleFull.java

...-util/src/main/java/de/vipra/util/model/ArticleStats.java

vipra-util/src/main/java/de/vipra/util/model/Sequence.java

vipra-util/src/main/java/de/vipra/util/model/Topic.java

vipra-util/src/main/java/de/vipra/util/model/TopicFull.java

vipra-util/src/main/java/de/vipra/util/model/TopicRef.java

vipra-util/src/main/java/de/vipra/util/model/TopicWord.java

vipra-util/src/main/java/de/vipra/util/model/Word.java