Nova parameters & decider parameters and proofs serialization

[arnaucube]

Adds serialization for

• Nova's ProverParams & VerifierParams
• Nova's DeciderEth ProverParams & VerifierParams & Proof Add also tests for it, which serve as examples of usage.

The idea is that with this PR, the full flow with Nova can be done with Prover's getting the serialized trusted setup parameters, and the Verifier getting the serialized proofs, inputs, and parameters, like they were from different instances/machines. An example of serializing and deserializing & verifying the proof (from the deserialized data) can be found at folding/nova/decider_eth.rs#L421 .

resolves #153

[czhang2718]

I needed to modify the import of your ark-circom for let nova_params = N::preprocess(&mut rng, &nova_preprocess_params).unwrap(); to run successfully.

I added rev = "18ca7f2".

[arnaucube]

This PR is now ready for review.