loongson/pypi: links for sage-numerical-backends-cplex

loongson/mirror sage_numerical_backends_cplex-10.4.tar.gz
loongson/mirror sage_numerical_backends_cplex-10.4rc3.tar.gz
loongson/mirror sage_numerical_backends_cplex-10.4rc2.tar.gz
loongson/mirror sage_numerical_backends_cplex-10.4rc1.tar.gz
loongson/mirror sage_numerical_backends_cplex-9.0b12.tar.gz
loongson/mirror sage_numerical_backends_cplex-9.0b9.tar.gz