SIOPv2 draft 11, OID4VP draft 18, SD-JWT, fixes

• Added:
  • Initial support for SIOPv2 draft 11
  • Initial support for OID4VP draft 18
  • SD-JWT support
  • Partial support for http(s) client_ids instead of DIDs. No validation for keys in this case yet though!
  • Convert presentation submissions that inadvertently come in from external OPs as a string instead of an object
  • Allow id-token only handling
  • Allow vp-token only handling
  • EBSI support
• Fixed:
  • issue with determining whether a Presentation Definition reference has been used
  • vp_token handling and nonce management was incorrect in certain cases (for instance when no id token is used)
  • Make sure a presentation verification callback result throws an error if it does not verify
  • Do not put VP token in the id token as default for spec versions above v10 if no explicit location is provided
  • Several small fixes