loongson/pypi: links for callbacks

loongson/mirror callbacks-0.3.0.tar.gz
loongson/mirror callbacks-0.3.0-py2-none-any.whl
loongson/mirror callbacks-0.2.0.tar.gz
loongson/mirror callbacks-0.1.3.tar.gz
loongson/mirror callbacks-0.1.1.tar.gz
loongson/mirror callbacks-0.1.tar.gz