feat(crypto): add crypto module with signature verification functionality

[yair-starkware]

This change is 

[ShahakShama]

Reviewable status: 0 of 4 files reviewed, 2 unresolved discussions (waiting on @yair-starkware)

a discussion (no related file):
What's the goal of this PR? why wrap starknet_crypto instead of just using it?

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src/crypto.rs line 52 at r1 (raw file):

        &signature.s.into(),
    )
    .map_err(|err| match err {

Extract to impl From
Also, why not just use starknet_crypto::VerifyError?

[yair-starkware]

Reviewable status: 0 of 4 files reviewed, 2 unresolved discussions (waiting on @ShahakShama and @yair-starkware)

a discussion (no related file):

Previously, ShahakShama wrote…

What's the goal of this PR? why wrap starknet_crypto instead of just using it?

discussed

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src/crypto.rs line 52 at r1 (raw file):

Previously, ShahakShama wrote…

Extract to impl From
Also, why not just use starknet_crypto::VerifyError?

I need to pass additional data for the error

[ShahakShama]

Reviewed 4 of 4 files at r1, all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @yair-starkware)

[ShahakShama]

Reviewed 1 of 1 files at r2, all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @yair-starkware)