update (ActiveMerchant::Billing::BraintreeGateway)

    # File lib/active_merchant/billing/gateways/braintree.rb, line 60
          def update(vault_id, creditcard, options = {})
            post = {}
            post[:customer_vault] = "update_customer"
            add_customer_vault_id(post, vault_id)
            add_creditcard(post, creditcard, options)
            add_address(post, creditcard, options)
            add_customer_data(post, options)

            commit(nil, nil, post)
          end