Make /admin and /moderation only accesible to Admins & Moderators

app/controllers/admin/base_controller.rb

@@ -0,0 +1,11 @@
+class Admin::BaseController < ApplicationController
+
+  before_filter :verify_administrator
+
+  private
+
+  def verify_administrator
+    raise CanCan::AccessDenied unless current_user.try(:administrator?)
+  end
+
+end