replaced deprecated ":dependent => true" statements

git-svn-id: http://redmine.rubyforge.org/svn/trunk@123 e93f8b46-1217-0410-a6f0-8f06a7374b81

app/models/document.rb

@@ -18,7 +18,7 @@
 class Document < ActiveRecord::Base
   belongs_to :project
   belongs_to :category, :class_name => "Enumeration", :foreign_key => "category_id"
-  has_many :attachments, :as => :container, :dependent => true
+  has_many :attachments, :as => :container, :dependent => :destroy
 
   validates_presence_of :project, :title, :category
 end