We've got a lot of these configured, but the AstroPay web site has newer info than the PDF we initially based them on. Update methods and submethods for each country based on info at https://developers.astropay.com/#cc_pm_codes
Create new submethod codes for Santander in different countries.
Update visa debit to use submethod code visa-debit
Add 'cash' method and submethods
in DonationInterface: astropay.adapter.php, DonationInterfaceFormSettings.php
in SmashPig: PaymentProviders\AstroPay\ReferenceData
in CRM: wmf_civicrm.install, wmf_civicrm.module (also fix mc-debit on line 569)