def self.up
  down
  rails_book_sku = Sku.find_by_sku("RAILS-B-00")
  ruby_book_sku = Sku.find_by_sku("RUBY-B-00")
  auto_book_sku = Sku.find_by_sku("AUTO-B-00")
  discount = Discount.create(:name => "Rails + Ruby Paper",
  :action => "DEDUCT_AMOUNT",
  :amount => "15.00")
  discount.skus = [rails_book_sku, ruby_book_sku]
  discount.save!
  discount = Discount.create(:name => "Automation Sale",
  :action => "DEDUCT_PERCENT",
  :amount => "5.00")
  discount.skus = [auto_book_sku]
  discount.save!
end
def self.down
  Discount.delete_all
end