updated readme
updated readme

ethereum/pyethapp,RomanZacharia/pyethapp,changwu-tw/pyethapp,d-das/pyethapp,heikoheiko/pyethapp,kustomzone/pyethapp,RomanZacharia/pyethapp,gsalgado/pyethapp,gsalgado/pyethapp,ethereum/pyethapp,danielnovy/test,changwu-tw/pyethapp,vaporry/pyethapp