Check the status of a refund

Class

Name	Type	Required	Description
`ADYRefundData`	NSObject		Instances of this class represent a refund on a particular transaction. A single transaction can have multiple refund instances. This is because a transaction can be refunded as a whole or partially. For example: when a customer purchased more than one item with one payment, but decides later on that one of the items is not satisfactory, only a part of the original transaction should be refunded. This can occur a number of times until all of the original amount has been refunded. The amount has to be refunded in the same currency as the original transaction.

Name	Type	Description
`pspReference`	NSString	The unique `pspReference` to identify this refund.
`amount`	NSNumber	The amount that was refunded.
`date`	NSDate	The date/time this refund was completed.
`reference`	NSString	A reference or description for this refund.
`processingState`	ADYProcessingState	The processing state of the refund, indicating if the refund was already submitted to the server or is waiting for a working internet connection. Can be ``ADYProcessingStateProcessed`` or ``ADYProcessingStateReversalPending``.