Migrate Jade to Pug template engine

Jade templates engine has been renamed to Pug.

We are using Pug already on the Blender Cloud repository, following is Flamenco and Attract

src/scripts/tutti/4_search.js

@@ -1,6 +1,6 @@
 /*
 * == Search ==
-* index and algolia settings are defined in layout.jade
+* index and algolia settings are defined in layout.pug
 */
 
 $(document).ready(function() {

src/scripts/tutti/7_user_search.js

@@ -1,5 +1,5 @@
 (function ( $ ) {
-    // See organizations/view_embed.jade for example use.
+    // See organizations/view_embed.pug for example use.
     $.fn.userSearch = function(algolia_application_id, algolia_public_key, algolia_index_users, on_selected) {
         var client = algoliasearch(algolia_application_id, algolia_public_key);
         var index = client.initIndex(algolia_index_users);