Improve admin product picker performance [ENG-781]
Validate line item's stock availabilty on complete! rather than all the time
Merge pull request #133 from bonobos/fix/product-picker-performance

Improve admin product picker performance [ENG-781]
Insufficient stock error handling in admin
Add OptionValue promotion rule.
Add admin interface for option value promo rule.
Add specs for option value promo rule.