spree/spree — pull request #4445 by HoyaBoya (2014-03-14 21:47:26+00:00)
Title: Fix promotion eligibility rules

In 2.1, prior to this change, a promotion's determination as to whether it has been applied to an order would always fail, since the order's calculation of whether a promotion credit exists compares against a promotion action, not a promotion. This change makes a promotion check whether its promotion actions have been applied to the order to see if it is on the order.

Colloboration with @pdamer, @athal7