Improve user feedback on the Profile > Design page

- Header changes immediately without a page reload
- Lets the user know that we actually saved their setting when changed

app/controllers/profile_controller.rb

@@ -9,7 +9,11 @@ class ProfileController < ApplicationController
 
   def update
     @user.update_attributes(params[:user])
-    redirect_to :back
+
+    respond_to do |format|
+      format.html { redirect_to :back }
+      format.js
+    end
   end
 
   def token