Release 2.2.1

Add Conversion Cancellation, Conversion Date Change and Conversion Split
Minor bug fixes

Release 2.1.5

Deprecate obsolete classes
Update classes to match API v2 spec and add RFC4627 compliant ToJSON method
Add Ibans, Transfers, VirtualAccounts and PaymentSubmission
Update FindParameters
Fix StringExtensions.ToSnakeCase regex
Add parameterless Find