Make Banners translatable

db/migrate/20180727140800_add_banner_translations.rb

@@ -0,0 +1,14 @@
+class AddBannerTranslations < ActiveRecord::Migration
+
+  def self.up
+    Banner.create_translation_table!(
+      title:       :string,
+      description: :text
+    )
+  end
+
+  def self.down
+    Banner.drop_translation_table!
+  end
+end
+