Deprecate proof parameter

[c2bo]

Closes #345

Removes the proof parameter in favour of always using proofs.

One point I wasn't sure about: To make the proofs object easier to parse , it always contains a parameter (named after the proof type) that contains a non-empty array. This means that for proofs of the type attestation, it contains an array containing exactly one JWT proof.

Are people fine with that choice?

[babisRoutis]

One point I wasn't sure about: To make the proofs object easier to parse , it always contains a parameter (named after the proof type) that contains a non-empty array. This means that for proofs of the type attestation, it contains an array containing exactly one JWT proof.

Are people fine with that choice?

Dear @c2bo

IMHO, that's a reasonable choice.