edx/edx-platform — pull request #5868 by dianakhuang (2014-11-06 14:35:29+00:00)
Title: Add a `created_at` field to OrderItem.

Hey guys, I've mentioned this to you guys. I've left the `created_at` field nullable to handle all the pre-existing `OrderItem`s that we don't have data for.

@adampalay @chrisndodge @jbau @ormsbee