the host, and whether the instance should be decorated as a "parent model"
     * of any event handlers.
     *
     *     // Customze property forwarding and event model decoration
     *     let TemplateClass = Polymer.Tempaltize.templatize(template, this, {
     *       parentModel: true,
     *       instanceProps: {...},
     *       forwardHostProp(property, value) {...},
     *       notifyInstanceProp(instance, property, value) {...},
     *     });
     *
     *
     * @namespace
     * @memberof P