test: add cross test suite
A new test suite has been created in order to test cross signature/validation. For each signer the rest of participants verifies the signature.
Notice there's a new npm script command to run: npm run test:cross
A new test suite has been created in order to test cross signature/validation. For each signer the rest of participants verifies the signature.
Notice there's a new npm script command to run: npm run test:cross