root/pypi: links for arithmetic

root/pypi arithmetic-0.6.2.tar.gz
root/pypi arithmetic-0.6.1.tar.gz
root/pypi arithmetic-0.5.tar.gz
root/pypi arithmetic-0.4.tar.gz
root/pypi arithmetic-0.3.tar.gz
root/pypi arithmetic-0.2.tar.gz
root/pypi arithmetic-0.1.tar.gz