remove storage_root attribute if present
remove storage_root attribute if present

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