Integration tests

[storojs72]

Current stack of solidity-verifier includes Rust, Python and Solidity environments. Rust implementations of pasta_curves, neptune and Nova are considered as "reference". Compatibility is an important requirement in mind for solidity-verifier that is why we use methodic of comparing test vectors produced from Rust "reference" software and consumed by Solidity contracts. We also use Python utility scripts inside the stack where we have some necessary algorithms implemented (uncompressing curve points + modular sqrt, splitting 256-bits field elements to 64-bit limbs). Those parts of the stack are not linked and enforced by CI and in case of any changes in "reference" software, compatibility may be broken, so we need some integration tests that convert our stack parts into the pipeline which we can enforce with a help of CI.