User can delete a payment type

[stevebrownlee]

Given the user is authenticated
When the user performs a gesture on the My Settings hyperlink in the navigation bar
And the user clicks on Payment Options
And the user clicks on the Delete hyperlink next to a payment type
Then the payment option will get deleted

Python students only, here's a tip: https://github.com/makinacorpus/django-safedelete/blob/master/safedelete/models.py