Fix https://github.com/richardkiss/pycoin/issues/57.
Fix https://github.com/richardkiss/pycoin/issues/57.

tomholub/pycoin,mperklin/pycoin,zsulocal/pycoin,ptcrypto/pycoin,Pan0ram1x/pycoin,Magicking/pycoin,Tetchain/pycoin,pycoin/pycoin,moocowmoo/pycoin,zsulocal/pycoin,Tetchain/pycoin,pycoin/pycoin,Kefkius/pycoin,mperklin/pycoin,shivaenigma/pycoin,devrandom/pycoin,gitonio/pycoin,thirdkey-solutions/pycoin,Treefunder/pycoin,XertroV/pycoin,richardkiss/pycoin,antiface/pycoin,shayanb/pycoin,antiface/pycoin,Treefunder/pycoin,Bluejudy/pycoin,richardkiss/pycoin,Pan0ram1x/pycoin,lekanovic/pycoin,Bluejudy/pycoin,lekanovic/pycoin,ptcrypto/pycoin,gitonio/pycoin,devrandom/pycoin,moocowmoo/pycoin,tomholub/pycoin,XertroV/pycoin,Kefkius/pycoin,shayanb/pycoin,thirdkey-solutions/pycoin,shivaenigma/pycoin,Magicking/pycoin