Added Token support to 2.0 (previously this was added for 1.1, but rathe...

Added in Token support for SagePay here. Adding and Removing a token are supported, updates are not support by Sage.

Repeat payments are also added here in DirectRepeatPaymentRequest, these allow you to use a previous transactions return codes to request another payment (without having to pass any card details or personal information, or to have to use a token, as not all accounts have Token support enabled by default)