Sale Promotion Coupon Module ############################ The sale_promotion_coupon module adds coupon to the promotions. A promotion with coupons will be applied only if a linked coupon has been added on the sale. Promotion Coupon **************** It defines the behaviours of a sets of coupon numbers for a promotion: - *Name*: The name of the coupon. - *Promotion*: The promotion to which the coupon is attached. - *Number of Use*: How much time a coupon number can be used. - *Per Party*: How the usage is counted. - *Numbers*: The list of numbers which must be unique.