added associations between cards and pages models

app/models/site_customization/page.rb

@@ -1,5 +1,6 @@
 class SiteCustomization::Page < ActiveRecord::Base
   VALID_STATUSES = %w(draft published)
+  has_many :cards, class_name: 'Widget::Card', foreign_key: 'site_customization_page_id'
 
   translates :title,       touch: true
   translates :subtitle,    touch: true

app/models/widget/card.rb

@@ -1,5 +1,6 @@
 class Widget::Card < ActiveRecord::Base
   include Imageable
+  belongs_to :page, class_name: 'SiteCustomization::Page', foreign_key: 'site_customization_page_id'
 
   # table_name must be set before calls to 'translates'
   self.table_name = "widget_cards"