Live regions need to be in the original HTML of
the page to work. We were generating the summary
in JS.
This changes the JS to only generate the contents
of the summary so changes to its contents are
announces by the existing live-region.
Expands the API of the macro to allow nested
checkboxes to have a summary tracking the current
selection, the fieldset to expand/collapse and
buttons to be added to allow jumping between
states.
Includes making 'Done' button inline on mobile.
Helps differentiate it form the form submit.