api cleanup

removed remaining files we are dropping from our framework
removed email support from WC_Email as this plug-in will be converted
into testimonial plug-in and we don't require order emails
removed api_request_url
removed shipping()
removed is_store_notice_showing
removed woocommerce_demo_store
removed woocommerce_demo_store_notice
removed woocommerce_variable_add_to_cart
begin removing usless wp_register_script and wp_enqueue_style that are
not in use
remove unused css from less before we recompile