Latest upstream with chargify unmerged commits

This represents the latest upstream active_merchant, as of Jun 04, 2014 and commit https://github.com/chargify/active_merchant/commit/0efd1e3444b270de8695ee397df3831c06cca8ce, with our chargify/active_merchant commits (which haven't been merged in to the upstream master) cherry-picked "on top".

Specifically, these commits:

![image](https://cloud.githubusercontent.com/assets/148323/3189897/61599bb4-ecc8-11e3-80c6-92b91260af8e.png)

https://github.com/chargify/active_merchant/commit/4c3101182653a49206dad3f1ca83c39756548e02
https://github.com/chargify/active_merchant/commit/4d532065e066397d7ec941e804fe5220976e52fb
https://github.com/chargify/active_merchant/commit/01247b14c7bebe9ea58540f4116e58b13c9bdbd5
https://github.com/chargify/active_merchant/commit/089ad332cfa4dc1306a67f70a3bf62bd7b2e1fc0
https://github.com/chargify/active_merchant/commit/6fe5671f1a917c2ff7b81fc68007e503c9b91c07

The motivation here is to get our fork of active_merchant as close to upstream as possible, since we have diverged significantly from it.