Modularize contracts package

[0xjei]

Description

This PR is intended to bring about the necessary improvements as stated in proposal #66.

To Do

• Create a Constants.sol file for the SNARK_SCALAR_FIELD and MAX_DEPTH constants.
• Update IMT implementations according to the proposal.
• Update tests
• Run benchmarks

Related Issue

See #66

Does this introduce a breaking change?

• Yes
• No

Other information

None

[0xjei]

Before

After

After #93 from @cedoor

[cedoor]

Hey @RayHuang880301 Could you also take a look at this PR to see if it's what you expected?

What is not clear to me yet is point 2 of your message:

For developers who want to use internal libraries to save run time gas costs, they can directly inherit IncrementalBinaryTreeInternal.sol to their main contract.

Libraries, from what I know, cannot be inherited. So, how could you use an internal function of a library in a contract?

[RayHuang880301]

Hey @0xjei @cedoor
Thank you very much for your work. It seems that this is exactly what I expected. 👍

Libraries, from what I know, cannot be inherited. So, how could you use an internal function of a library in a contract?

Because a library is used here instead of a contract, so as you said, import should be used here instead of inherit. It looks good to me now. Thank you!

[0xjei]

Hey @0xjei @cedoor Thank you very much for your work. It seems that this is exactly what I expected. 👍

Libraries, from what I know, cannot be inherited. So, how could you use an internal function of a library in a contract?

Because a library is used here instead of a contract, so as you said, import should be used here instead of inherit. It looks good to me now. Thank you!

Thank you @RayHuang880301 :) @cedoor, green lights