* add error handling
* change error name
* Error types oriented around the primary types we expose in the zebra-chain API
* Fix Ok spelling
* orchard::note::new(): return NoteError if randomness produces invalid Pallas point
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Co-authored-by: Deirdre Connolly <durumcrustulum@gmail.com>
Co-authored-by: teor <teor@riseup.net>