[Feature Request] Support for more validation options

[sazzer]

Hi there,

Biscuit has been great for working with JWTs, but I've found when working with some - Cognito ones in particular -that I need to do some more extensive validation myself.

In particular, with Cognito I need to:

• Validate that the token_use claim is present and has the correct value.
• Validate that the username claim is present.

With Biscuit, as best I can tell, I can only validate the standard set of claims, and I need to then do additional validation myself on these extra ones. It would be really useful if there was some way to include these claims in the standard validation that is done by the Compact::validate() call.

Cheers