Schema changes
Fix specs
Cart form type
Prevent property access error
Fixed missing base url in javascript session
Fix tests
Fix grammar issue
Changed the relation between Coupon and Order to unidirectional
Replace set coupon code step with something without implementation details
Make the Promotion component using multiple coupons by default
Added schema migration
Covered case when coupon is removed
Add license to migration
Fix tests after rebase
Merge pull request #1676 from umpirsky/fix/issue-1499

Multiple coupon per order
Support per-user limits on coupons. This restricts users from placing multiple
orders with the same discount. This is a commonly used feature in Magento for sites
that have a max $ limit on their coupons. Users bypass this by placing multiple orders.
Magento however doesn't force you to be logged in during the time of ordering,
so it's easily bypassed that system.