Adds cost to option values.
Add following line to your Gemfile:
gem 'spree_option_value_cost', :git => 'git://github.com/alekseev/spree-option-value-cost.git'
Then run this commands:
rake spree_option_value_cost:install:migrations
rake db:migrate
Copyright (c) 2011 Denis Alekseev, released under the New BSD License