loongson/pypi: links for pyconvert

loongson/mirror pyconvert-0.6.3.tar.gz
loongson/mirror pyconvert-0.6.2.tar.gz
loongson/mirror pyconvert-0.6.1.tar.gz
loongson/mirror pyconvert-0.3.alpha.tar.gz
loongson/mirror pyconvert-0.2.alpha.tar.gz