2022-01

Further improvements to algorithm to detect account duplication covering the following scenarios:
- Changes in masked characters
- Changes in masked lengths, in the situation when an institution decides to reveal additional digits in account number
- Changes in BSB e.g. an institution decides to remove BSB
- Characters going from unmasked to masked
Added 403 Invalid request HTTP error response for when there has been too many requests for the token endpoint within a 5 minute period from a specific IP address.