[REF] Start to convert Dummy processor to use PropertyBag
Created by: eileenmcnaughton
This starts the process of adopting the new property bag - but in the Dummy processor rather than a live processor
Uses the array
Casts to the bag
@artfulrobot @mattwire I'm thinking this will throw an error on tests in setAmount per previous - but it occurred to me that the Dummy processor was a good one to convert first as it's more used by devs & less by live sites.
Also, I added preferred functions for doCancelRecurrring - really we should also rename doDirectPayment to doPayment as part of modelling preferred practice
Note $params IS still being accessed in this class - for credit card variables. We haven't got those handled as yet on the PropertyBag - if we merge this we should review those next