* Pulls in some traits and methods from curve25519-dalek around the
vartime multiscalar multiplication.
* Move scalar mul things we want to upstream to jubjub to their own crate
* Make Verify agnostic to the SigType
Co-authored-by: Henry de Valence <hdevalence@hdevalence.ca>
Co-authored-by: Jane Lusby <jlusby42@gmail.com>
The `SpendAuth` test vectors were generated using
`FixedGenerators::SpendingKeyGenerator`, and the `Binding` test vectors
were generated using `FixedGenerators::ValueCommitmentRandomness`.
This ran into problems with Clone/Copy bounds -- it seems like the
derived impls require that the phantom type T also be Clone / Copy /
Debug for the type to be. This commit does a hacky fix that makes it
work for now, but it should be cleaned up later.