apply(el: Element | default, selector: string, func: (el: Element | ServerElement) => void): Promise<void[]>
Take a target DOM element and a selector to apply to that element
and run a function on every match. A promise is returned so that
the result can be awaited - important in the server context
where we want all asynchronous updates can complete before the
response is sent
Helpers for rendering in WaferServer