support slug and url

[twilson63]

/notes/note-{wallet[3] + wallet[3] + slug}

This will make the unique identifier of the note the wallet short code plus the slug of the note and each interaction would a new transaction id. The notes endpoint should support either {txId} or {slug}, this will allow for backward compatibility and if users want to pin a specific revision. The note should use the same "like" contract if it is the same owner?

Maybe prefix it with note-{slug} this will allow the app to know it is a slug not a txId