add: initialize blockchain; adding blocks; removed: block_score persistence (let's optimize later)
add: initialize blockchain; adding blocks; removed: block_score persistence (let's optimize later)

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