code: public void addString(int key, String value) {
          PebbleTuple t =
                  PebbleTuple.create(key, PebbleTuple.TupleType.STRING, PebbleTuple.Width.NONE, value);
          addTuple(t);
      }
docs: Associate the specified String with the provided key in the dictionary. If another key-value pair with the same
  key is already present in the dictionary, it will be replaced.
  
  @param key
  key with which the specified value is associated
  @param value
  value to be associated with the specified key