refactor: object serialization when sending blocks
refactor: object serialization when sending blocks

karlfloersch/pyethereum,shahankhatch/pyethereum,ckeenan/pyethereum,holiman/pyethereum,jnnk/pyethereum,ddworken/pyethereum,ethermarket/pyethereum,shahankhatch/pyethereum,pipermerriam/pyethereum,harlantwood/pyethereum,vaporry/pyethereum,ethereum/pyethereum,pipermerriam/pyethereum,karlfloersch/pyethereum,ethers/pyethereum,inzem77/pyethereum,ethereum/pyethereum