fix relation between bulletin and category (news also)

vendor/built_in_modules/announcement/app/models/bulletin_category.rb

@@ -17,7 +17,7 @@ class BulletinCategory
   
   has_one :i18n_variable, :as => :language_value, :autosave => true, :dependent => :destroy
   
-  has_many :bulletins
+  has_many :bulletins,:dependent => :destroy
   
   def pp_object
     i18n_variable[I18n.locale]

vendor/built_in_modules/news/app/models/news_bulletin_category.rb

@@ -17,7 +17,7 @@ class NewsBulletinCategory
   
   has_one :i18n_variable, :as => :language_value, :autosave => true, :dependent => :destroy
   
-  has_many :news_bulletins
+  has_many :news_bulletins,:dependent => :destroy
   
   def pp_object
     i18n_variable[I18n.locale]