remove tabs in constants.pyx
remove tabs in constants.pyx

introduced in e2aae960d9c0b7aecd6b3fa36bf4ec1a33be2ddf


swn1/pyzmq,ArvinPan/pyzmq,yyt030/pyzmq,caidongyun/pyzmq,dash-dash/pyzmq,dash-dash/pyzmq,Mustard-Systems-Ltd/pyzmq,Mustard-Systems-Ltd/pyzmq,swn1/pyzmq,caidongyun/pyzmq,Mustard-Systems-Ltd/pyzmq,swn1/pyzmq,ArvinPan/pyzmq,dash-dash/pyzmq,caidongyun/pyzmq,yyt030/pyzmq,ArvinPan/pyzmq,yyt030/pyzmq