code: @Override
      public void incrementDocCount(String word, long howMuch) {
          T element = extendedVocabulary.get(word);
          if (element != null) {
              element.incrementSequencesCount();
          }
      }
docs: Increment number of documents the label was observed in
  
  Please note: this method is NOT thread-safe
  
  @param word the word to increment by
  @param howMuch