Added models, management commands and migrations for Coupons.

[freakboy3742]

No description provided.

[coveralls]

Coverage decreased (-0.5%) to 99.522% when pulling 3f9919a on jambonsw:coupons into d12c367 on pinax:master.

[coveralls]

Coverage decreased (-0.5%) to 99.522% when pulling 3f9919a on jambonsw:coupons into d12c367 on pinax:master.

[paltman]

@freakboy3742 good stuff. Really appreciate all the contributions. I'd like to preserve the 100% coverage. Would you mind adding a couple tests for the __str__ method on Coupon?

[coveralls]

Coverage decreased (-0.2%) to 99.841% when pulling 2811813 on jambonsw:coupons into d12c367 on pinax:master.

[coveralls]

Coverage decreased (-0.2%) to 99.841% when pulling 2811813 on jambonsw:coupons into d12c367 on pinax:master.

[coveralls]

Coverage decreased (-0.2%) to 99.841% when pulling 2811813 on jambonsw:coupons into d12c367 on pinax:master.

[coveralls]

Coverage remained the same at 100.0% when pulling 5a5ee0b on jambonsw:coupons into d12c367 on pinax:master.

[paltman]

Thanks!