26739: Sort modal for mobile, dropdown for desktop:
* Generate vn-sort-search files and make them gruntable.
* Add flag to only show sort directive on search pages
* Port enquire stuff from theme controllers into vn-faceted-search directive where it belongs
* Add flag for sorting accordion
* Added style and markup for sort elements.
* Make clicks functional
* Clean up style
* Prototype for mobile (instead of sliding screen)