Add support for request-before-update, request-success attribs on popup fields

This PR adds support for `data-request-success` and `data-before-update` attributes on elements that open popup data controls so they're more in line with the rest of the october JS framework.

## Example usage
```html
<a href="#" data-control="popup" data-handler="onOpenModal" data-request-success="alert('hi')" class="btn btn-default btn-sm oc-icon-plus">Test</a>
```