Use unique TxnId
Always set Klarna test mode fields
TxnId is actually optional
Merge pull request #1174 from Shopify/fix-klarna-test-mode

Always set Klarna test mode fields
Payex: Add FI as a supported country

Closes #1084.
Stripe: Allow for updating of stored card

Note: this is a potentially breaking API change, as it changes the
definition of #update to match standard ActiveMerchant.

Closes #1018.
Authorize.Net: Separate ARB out from main gateway

ARB is outside the scope of ActiveMerchant and will be deprecated in the
future. In addition, even the functionality in AM shares no code with
the standard Auth.Net code.

This splits ARB into its own gateway in preparation for removal. We will
deprecate it for now, and see if there is anyone who wants to pick up
maintenance of it in a separate gem, before finally removing it from the
code base.

Closes #1047.
Authorize.Net ARB: Fix tests
Authorize.Net CIM: Add recurring billing flag

Closes #1088.
Spreedly: Add support for :ip

Closes #1090.
PayPal Express: Improve received_at handling

Closes #1105.
PayPal Express: Add ReqBillingAddress flag

Closes #1118.
Remove extraneous Klarna test
Beanstream: Add support for single use tokens

Closes #997.
Closes #1126.
PayPal Digital Goods: Allow mobile

Closes #1138.
PayPal Express: pass logo image for setup request

Closes #1144.
Maxipago: Add installment support

Closes #1145.
Improve credit card validation

Previously, if you specified an invalid card number and you specified a
nil brand, you'd get two validation messages:

* card type can't be blank
* number is invalid

When your form doesn't allow you to specify a brand, that first error
message is confusing to users.

So now, we only validate the brand if the number is legitimate.

Closes #1171.
Deprecate recurring functionality

There is too much variance between the recurring functionality provided
by gateways for ActiveMerchant to do a good job of abstracting it. Thus
this deprecates all such functionality with the intention of stripping
it out completely at some future point.

Note that this does *not* refer to tokenization support, but rather the
ability to set up and manage the ability some gateways support to
automatically charge a card on a recurring basis.
Merge pull request #1175 from Shopify/pxpay_amount_fix

Fix repeat PxPay transactions