code: public static <D extends DifferenceEngineConfigurer<D>>
          D withPlaceholderSupport(D configurer) {
          return withPlaceholderSupportUsingDelimiters(configurer, null, null);
      }
docs: Adds placeholder support to a {@link DifferenceEngineConfigurer}.
  @param configurer the configurer to add support to
  @return the configurer with placeholder support added in