code: public Hbs doWith(final Consumer<Handlebars> callback) {
      requireNonNull(callback, "Configurer is required.");
      return doWith((hbs, conf) -> callback.accept(hbs));
    }
docs: Set a handlebars callback.
  
  <pre>{@code
  {
  use(new Hbs().doWith((hbs, conf) -> {
  ...
  });
  }
  }</pre>
  @param callback Configurer callback.
  @return This module.