Overlay relative to the first relative parent

As in CSS, a Child with an absolute position relates its position to the first Parent with a relative position.

This could be possible when setting overlays in Prototype if you add a few options in Prototype mode:

1. Set as relative - option available for the element selected, same as “Scroll behaviour” shows when selecting an element;
2. Listen to the first relative parent - option available for any overlay and when that is enabled the overlay positions itself to the first relative parent instead of the element that is used to trigger it.

This should not break existing prototypes.