Restores acts_as_tree instance methods removed in r10919.

git-svn-id: svn+ssh://rubyforge.org/var/svn/redmine/trunk@10923 e93f8b46-1217-0410-a6f0-8f06a7374b81

lib/plugins/acts_as_tree/lib/active_record/acts/tree.rb

@@ -47,6 +47,8 @@ module ActiveRecord
           has_many :children, :class_name => name, :foreign_key => configuration[:foreign_key], :order => configuration[:order], :dependent => configuration[:dependent]
 
           scope :roots, where("#{configuration[:foreign_key]} IS NULL").order(configuration[:order])
+
+          send :include, ActiveRecord::Acts::Tree::InstanceMethods
         end
       end