Add migration to create a new field on BlogPosts for custom teasers.

db/migrate/7_add_custom_teaser_field_to_blog_posts.rb

@@ -0,0 +1,10 @@
+class AddCustomTeaserFieldToBlogPosts < ActiveRecord::Migration
+  def self.up
+    add_column :blog_posts, :custom_teaser, :text
+  end
+
+  def self.down
+    remove_column :blog_posts, :custom_teaser
+  end
+end
+