Adds the $look_in_self parameter for was::locate_template() which allows the function to also check for a given template in the plugins 'templates' folder.
Introduces was::get_header() and was::get_footer() which are essentially proxies for their built-in counterparts. Difference is that these methods also look in the 'subshops' folder, of the current theme, for the header or footer template before falling back to WP hierarchy.