Quickpay integration: Fix v6 response parsing

The regexp didn't work with the actual input directly from Quickpay.

Closes #661.
First Data e4: Add store support via TransArmor

TransArmor is an API extension for implementing card number
tokenization.

Closes #563.
MerchantWarrior: Format expiration correctly

According to the MerchantWarrior API documentation, cardExpiryYear and
cardExpiryMonth must meet these conditions:

  cardExpiryMonth
  Example: 05
  Notes: This must be in MM format. The month must be zero-padded if
         it’s less than 10.
  Valid Length: 2 digits.

  cardExpiryYear
  Example: 13
  Notes: This must be in YY format.
  Valid Length: 2 digits.

Closes #665.
Add iconv for ActiveSupport 2.3 under Ruby 2.0
Require Ruby 2.0 compatibility in Travis-CI

Closes #669.
Fix duplicate test methods

A bunch of test methods were duplicated, meaning the first version of
them was not being run. This was revealed by running under Ruby 2.0,
since its test/unit warns about the duplication.
DataCash: Fix remote tests

Closes #670.
Fix GettingStarted.md reference links in README

Closes #671.
Add Transnational gateway

http://www.tnbci.com/

Closes #675.
Authorize.Net: Add Check as a payment method

Closes #676.
Merchant e-Solutions: Add ref# and recurring

Adds client_reference_number on each operation and enables recurring
operations.

Also catches 404's from MeS if URL is wrong because of MeS system issue.

Closes #648.
Bogus gateway: Add authorization to response

Most (if not all) gateways add 'authorization' to response of purchase
transaction. It allows developer to use returned 'authorization' as a
payment source for subsequent transactions in some
gateways (PayJunction for example).

To test this behavior properly it makes sense to have BogusGateway to
return 'authorization' in purchase response too.

Closes #677.
Bluepay: Add Check support; general cleanup

Brought the gateway into better alignment with AM coding standards.

Also fixed an issue with the wrong value being passed for checking
accounts. Unable to get a passing remote test due to not having a test
account set up for checks, but the new error looks more reasonable.

Closes #678.
Dwolla: Security fix and enable guest checkout

Patches major security holes and enables the Guest Checkout feature.
This fix has been much needed since the last release in 2011.

Closes #679.
SagePay gateway: Per-transaction 3DS selection

Added 3D secure flag, so users can enable/disable per transaction.

Closes #681.
Barclays ePDQ: Handle incorrectly encoded response

When an order contains non-standard characters (normally in the
customer's address and is normally accented characters) and is submitted
to Barclays, they will send back an XML response flagged as UTF-8 but is
actually ISO-8859-1. This causes parsers like REXML to raise an
exception while parsing what it thinks is UTF-8.

Barclays has acknowledged this issue is on their end and said they have
no plans on fixing it.

Fixed by forcing the encoding of all responses to ISO-8859-1.

Closes #588, #683.
Orbital: Bug fixes and added fields

Fixes a bug with phone number.

Adds CustomerEmail, Retry Logic, Managed Billing, and Destination
Address (partial building blocks for Level 2 and Level 3 Data, Bill Me
Later & Safetech).

Closes #684.
Distinguish invalid/empty issue_number errors

CreditCards now give a clearer error message when the issue_number is
unexpectedly blank.

Closes #667.
Float Rails to the latest version

Also fixes a Mocha error in some permutations.

Closes #685.
USA ePay Advanced: Fix Check support

Closes #596.