Add native support for eth_estimateGas and debug_traceTransaction

[spilin]

It is possible to add support for eth_estimateGas and debug_traceTransaction using standalone-refiner as a source. Key missing peace is a communication channel between refiner and relayer to proxy request. As a suggestion on how to send messages between to services - sockets(UNIX/tcp) seems like an obvious choice. We should investigate it and discuss