Fixes #140 - issue with the 'capture' argument passable to https://strip...

...e.com/docs/api#create_charge. Currently being sent as 'captured' instead of 'capture'
I think there is one more spot that needs this correction: https://github.com/lukeburden/django-stripe-payments/blob/master/payments/models.py#L872

Can you take care of that?

Thanks!