code: public WikiParameters addParameter(String key, String value)
      {
          WikiParameters result = new WikiParameters();
          result.fList.addAll(fList);
          result.fList.add(new WikiParameter(key, value));
          return result;
      }
docs: Creates a new copy of this parameter object with new specified key/value
  pair.
  
  @param key the parameter name
  @param value the value of the parameter
  @return a new copy of parameters object with the given key/value pair