Andrew Davis

**Description** [debug_traceTransaction](https://docs.nethermind.io/interacting/json-rpc-ns/debug/#debug_tracetransaction) is giving negative `gasCost` values for `STOP` and `RETURN` opcodes. **Steps to Reproduce** Grab the transaction trace eg. ```bash curl -X POST http://localhost:8545 \ --data '{"jsonrpc":"2.0","method":"debug_traceTransaction","params":["0x48b7c61378bbd2fff08912109815161f5835735a0b6cbec9d0c7ef72b31619fb",{}],"id":1}' \ -H...

Add Makefile for streamlined build process and update README with sim…plified instructions