[Openid-specs-fapi] Updating FAPI Version

[Anders Rundgren]

Since there will be a continued need for updating Open Banking APIs, and at any time, I'm suggesting another method:
https://cyberphone.github.io/doc/research/casting-apis-in-stone.pdf

"Stove Pipe" APIs of the kind that banks are used to are simply put not agile enough.  Using cryptography, even publicly accessible lookup data can be secured.

Anders