Sub-menu Container Attributes
So looking at the available list of array properties that can be used to create a menu, there is no property to pass other attributes to them.
To achieve the Foundation 6 structure I had to do this: 'subcontainer_tag_class' => array('menu vertical" data-dropdown-menu="')
So the request is to be able to to add other attributes to menu containers and/or their items.
Edit: apparently my text gets converted to HTML (you might want to fix that?), here's the Foundation 6 link for dropdown menus, http://foundation.zurb.com/sites/docs/dropdown-menu.html