Added toggle to compliment show and hide for RJS

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@3329 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

actionpack/lib/action_view/helpers/prototype_helper.rb

@@ -454,6 +454,11 @@ module ActionView
           call 'Element.hide', *ids
         end
         
+        # Toggles the visibility of the DOM elements with the given +ids+.
+        def toggle(*ids)
+          call 'Element.toggle', *ids
+        end
+        
         # Displays an alert dialog with the given +message+.
         def alert(message)
           call 'alert', message