Upgrade Slate sample to Slate 1.5

Closes gh-361

samples/rest-notes-slate/slate/source/javascripts/app/_toc.js

@@ -1,3 +1,4 @@
+//= require ../lib/_jquery
 //= require ../lib/_jquery_ui
 //= require ../lib/_jquery.tocify
 //= require ../lib/_imagesloaded.min
@@ -47,6 +48,7 @@
   $(function() {
     makeToc();
     animate();
+    setupLanguages($('body').data('languages'));
     $('.content').imagesLoaded( function() {
       global.toc.calculateHeights();
     });