Drop EncryptedCreditCard model

Only reason to have it in place was to skip cc number validation which
can now be skipped by providing a encrypted_data attribute on CreditCard
object

See https://github.com/spree/spree/commit/7654107c2482779ef77c31f7958933bf17d87ac9
Save proper recurring reference when creating profiles

Assume the last recurring details belongs to the card just submitted by
the customer. When using client encryption I can't think of a way to be
absolutely sure which recurring detail matches the one just provided by
the customer
Set up a spec to reach adyen api

Useful to do some quicking testing to ensure creating profiles is
working as expected (without having to manually go through browser and
repeat a bunch of steps)