#569 adding return values to NodeElement so action method chaining be p...

In continue to #569 suggestion, here is PR
it is correct. clickLink searches the link, which is always a NodeElement, even when ``$this`` is the page.

However, I'm not sure we should make this method return the link. It may be confusing as it is **not** a fluent interface (it is not ``$this`` being returned).