Load admin bar backbone with noConflict.

This is to avoid conflicts with Backbone on the about pages until
Backbone is in the main JS lib.

r2/r2/public/static/js/adminbar.js

@@ -1,3 +1,5 @@
+(function(Backbone) {
+
 r.adminbar = {}
 
 r.adminbar.AdminBar = Backbone.View.extend({
@@ -209,3 +211,5 @@ $(function() {
         r.adminbar.browserTimings.fetch()
     }, 0)
 })
+
+})(Backbone.noConflict())