Upgrade to snarkVM

[howardwu]

Motivation

This PR upgrades the aleo-setup repository to snarkVM on the testnet2 branch, which uses hash to curve for curve generators and all cryptographic primitives related to account derivation for this repository.

• Upgrades all usage of rand to v0.8 and enforces CryptoRng across the board
• Removes all usage of rand_xorshift in favor of rand_chacha to enforce CryptoRng
• Deprecates all usage of snarkOS-toolkit in favor of snarkVM-dpc
• Updates CI to use Rust 1.53.0
• [Critical] Changes signature format to have unambiguous serialization, please observe the new approach:

// Before
let signature_string = view_key.sign(&message.into_bytes(), rng)?.to_string();
let signature_struct = Signature::from_str(&signature_string)?;

// After
let signature_string = hex::encode(view_key.sign(&message.into_bytes(), rng)?.to_bytes_le()?);
let signature_struct: <<Testnet2Parameters as Parameters>::AccountSignatureScheme as SignatureScheme>::Signature = FromBytes::from_bytes_le(&hex::decode(signature_string)?)?;

Remarks

aleo-setup/phase2 needs to be reviewed in detail, it is very much out of date at this point. Most notably, some things to watch out for are:

• There exists a seeded ChaChaRng based hash_to_g2 implementation in here.
• There exists legacy/inefficient converters for compatibility with libzexe which is deprecated.
• The aleo_compatibility integration test is commented out, given we do not need to cross-check anymore. This file should not be deleted, but rather updated to sanity check the Phase2 execution. Please see the equivalent phase1/tests/marlin.rs file to see how this conversion was done.

The same applies for the setup2 module. Most notable:

• [Critical] The rng in Setup2::new() was previously hardcoded terribly as XorShiftRng::from_seed([0u8; 16])
• This module is now pegged to snarkvm_dpc::testnet2 however the instantiation of this inside setup2 has not been inspected.
• There exists legacy/inefficient converters for compatibility with libzexe which is deprecated.