use cors middleware instead of plugin, so no need to add OPTIONS method to each url
use cors middleware instead of plugin, so no need to add OPTIONS method to each url

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