"vp" vs. "verifiable_presentation"

[djvs]

After some examination @ Bloom (original authors of spec) we noticed that the VP sharing under the key verifiable_presentation is somewhat needlessly disjoint from the JWT VP spec which otherwise closely overlaps with it. We've partially moved internally to preferring the key vp for this reason.

I'm a little out of the loop on how this spec is being maintained and would like to suggest modifying that key generally, or less preferably, accepting both. Happy to submit a PR to this effect if that's acceptable to all.