Merge pull request #101 from spookylukey/master

GlobalIris: Added missing item for serialising CreditCard
GlobalIris: support CreditCard.cardholders_name in auth requests
Tests: skip WorldPay tests if insufficient configuration
GlobalIris: added support for 3 additional pieces of data that can be sent to RealAuth

Includes docs and tests
GlobalIris: Added support for strange address 'code' needed for AVS checks
Merge pull request #102 from spookylukey/global_iris_fixes

Global iris fixes
Global Iris: Added test for RealAuth request with MPI information
Global Iris: Added test for parsing RealAuth 'success' XML
Global Iris: pass additional AVS data back from RealAuth responses in gateway response dictionary