DO NOT MERGE: GLV Implementation

[missac213]

DO NOT MERGE: Move to OpenZL.

Changes:

• manta-crypto/src/glv: GLV scalar product implementation, including sage scripts which compute the GLV parameters for BLS and BN and correctness tests.
• manta-benchmark: Added Benchmark trait and implemented it for GLV, which is now benchmarked. It shows the expected performance improvement. TODO: implement Benchmark trait for the other benchmarked functions, I plan to do this as part of DO NOT MERGE: Feat/test benchmark suite crypto primitives #208. Also planning to expand benchmark/ecc to the BN curve in that PR.

Performance Benefits: 31% less constraints in R1CS. See https://www.notion.so/mantanetwork/Scalar-multiplication-of-elliptic-curves-194a4e70a4f943a7acbab549d4331a4d for the full details.

Closes #209

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• Linked to an issue with discussion and accepted design OR have an explanation in the PR that describes this work.
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• Checked that changes and commits conform to the standards outlined in CONTRIBUTING.md.

[bhgomes]

Another comment:

The file structure for the benchmarking library is a bit complicated. I would recommend the following flatter structure:

    - manta-benchmark
      - src
          - lib.rs (contains Benchmark trait)
          - glv.rs (contains GLV impl of Benchmark trait)
          - ecc.rs (contains ECC benchmark definitions)

Also, see my notes in the manta-crypto/src/glv/mod.rs file on moving the AffineCurveExt trait.

all changes implemented, merging