loongson/pypi: links for retinex-for-mri

loongson/mirror retinex_for_mri-0.2.9.tar.gz
loongson/mirror retinex_for_mri-0.2.7.tar.gz
loongson/mirror retinex_for_mri-0.2.6.tar.gz
loongson/mirror retinex_for_mri-0.2.5.tar.gz