Order payment engines by name

In our case, the bank account will show before the creditcard. That is what
we wanted.

![screen shot 2014-09-19 at 11 08 31 am](https://cloud.githubusercontent.com/assets/230476/4339852/fca951ce-4027-11e4-9fb1-439520da1abe.png)


It is related to #609.