Move promotion code generation into a reusable object.
Merge pull request #18 from isaacgrant/promotion-code-generator

Move promotion code generation into a reusable object.
Fix updating OrderCommissionTotalView as part of a create script.

Cast the returned order total so that column types do not change, and replacing the view works.
Merge pull request #20 from isaacgrant/how-do-you-solve-a-problem-like-maria

Fix updating OrderCommissionTotalView as part of a create script.