Use clone to copy class methods in 1.8.7

In Ruby 1.8.7 (but not 1.8.6 or 1.9), Object#dup does not copy an
object's singleton methods.  CUrrently, resources_controller exposes
this difference with a duped module that lacks the included callback of
its original.  This can be worked around by simply invoking #clone
instead, which does not suffer from this problem.

lib/ardes/resources_controller/include_actions.rb

@@ -16,7 +16,7 @@ module IncludeActions
       def include_actions(controller, options = {})
         options.assert_valid_keys(:only, :except)
         raise ArgumentError, "you can only specify either :except or :only, not both" if options[:only] && options[:except]
-        mixin = self.dup
+        mixin = self.clone
         action_methods_to_remove(options).each {|a| mixin.remove_action_method(a) }
         controller.send :include, mixin
       end
@@ -36,4 +36,4 @@ def action_methods_to_remove(options = {})
       end
     end
   end
-end
+end