code: public static <T> List<ConfigurationInfo<T>> newList(boolean isOptional, T location) {
      if (location == null) {
        throw new IllegalArgumentException("location cannot be null");
      }
      return newList(Collections.<T>singletonList(location), isOptional);
    }
docs: Creates a list of configuration infos from the single location and if they are
  optional.
  
  @param <T> the type of location. Only {@code String} and {@code URL} are
  supported.