Improve bc_transaction_test test.
Improve bc_transaction_test test.

richardkiss/pycoin,moocowmoo/pycoin,moocowmoo/pycoin,mperklin/pycoin,Magicking/pycoin,richardkiss/pycoin,zsulocal/pycoin,zsulocal/pycoin,XertroV/pycoin,Magicking/pycoin,shivaenigma/pycoin,shivaenigma/pycoin,pycoin/pycoin,XertroV/pycoin,pycoin/pycoin,shayanb/pycoin,mperklin/pycoin,shayanb/pycoin