During the certification process, found out that CurrencyCode and
CurrencyExponent were not being set while performing transactions with saved
profiles.  This commit fixes that.
tests for orbital_mandatory_field_fix ee1a3ff
i missed a syntax error...
Ipay88: Use the amount in dollars instead of cents to generate the signature.
Add bitpay return, fix return_url mapping
fixes #770 purchase with card token or card id

Stripe supports charging a card token or a customer's card.
A card number only be passed with an associated customer.

Both methods are documented:

"If you also pass a customer ID, the card must be the ID of a card
belonging to the customer. Otherwise, if you do not pass a customer
ID, the card you provide must either be a token, like the ones returned
by Stripe.js, or a dictionary containing a user's credit card details"
    - https://stripe.com/docs/api#create_charge

Resolved this issue by allowing the api user to pass in flags in the
options hash.

a) options[:is_token] :
    charging a card token
b) options[:is_customer_card_id] :
    charging a customer's card.
    options[:customer] should also be included.

Request parameters.
a) Charging a card token:
curl https://api.stripe.com/v1/charges \
   -u sk_test_NMgf6M5lzRW3Vp345LJvR6Ua: \
   -d amount=208973 \
   -d currency=usd \
   -d card=tok_2DWWZ7t5sJQZPt \
   -d "description=Charge for test@example.com"

b) Charging a charging a card id.
{
    amount: "90707"
    currency: "usd"
    customer: cus_2IJycssqIpDju6
    card: cc_2IJy79OB3PjOCh
    description: "Spree Order ID: R252432727-AEWE8QED"
    payment_user_agent: "Stripe/v1 ActiveMerchantBindings/1.36.0"
}
Add regression tests for #797
[stripe] Update remote tests to account for Stripe's API changes
Webpay: Override add_customer method.
Merge pull request #879 from Shopify/bitpay_add_return

Add bitpay return, fix return_url mapping
Revert "Paymill: Add support for specifying the :customer"

This reverts commit 75744b7b2302055f74a286344b5508ead33cce59.

Conflicts:
	CHANGELOG
Bump for release v1.40.0
Merge pull request #873 from Shopify/ipay88-fix

Ipay88: Use the amount in dollars instead of cents to generate the signature
Stripe: Ignore tthe customer option when paying with a creditcard.
Merge pull request #886 from Shopify/stripe-fixes

Stripe: Ignore tthe customer option when paying with a creditcard.
Add Conekta gateway

https://conekta.io

Closes #863.
Wirecard: Add support for void and refund

Closes #887.
Merge pull request #865 from juicedM3/orbital_mandatory_field_fix

Orbital mandatory field fix
Bump for release v1.41.0
Fix NoMethodError "tr" for params with dash

Also fixes a nil being passed to CGI.unescape.

Closes #890.