anchor.diff:      }
     }
   
  +  /**
  +   * changes the name of a user and returns true if possible.
  +   * Requires the old username, the password and a new name
  +   */
     Future<bool> changeUserName(String oldName, String pwd,
         String newName) async {
       if (!_available) return new Future.value(false);
  
positive.code:     }
    }
  
    //>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
    Future<Map> loginUser(String name, String pwd) async {
      Map map = new Map();
      if (!_available) return new Future.value(false);
  
negative.code:     }
    }
  
    /**
     * Changes the password of the user to a new one and returns true if possible.
     * Requires the username, the old password and the new password
     */
    Future<bool> changeUserPassword(String name, String oldPW,
        String newPW) async {
      if (!_available) return new Future.value(false);
  