onElementRender incorrect documentation

[mmiller42]

Looks like the onElementRender callback takes two parameters: the Form.IO instance and the element. Also, the documentation should state that the onElementRender handler must return the element to render (if it does not return anything, the form does not render).

[mmiller42]

Also, looks like npm test isn't set up in master and all the builds are failing.

[randallknutson]

This no longer applies to the current version of the renderer.