root/pypi: links for flow2

root/pypi flow2-6.0.0rc13.tar.gz
root/pypi flow2-6.0.0rc12.tar.gz
root/pypi flow2-6.0.0rc11.tar.gz
root/pypi flow2-6.0.0rc10.tar.gz
root/pypi flow2-6.0.0rc8.tar.gz
root/pypi flow2-6.0.0rc7.tar.gz
root/pypi flow2-6.0.0rc6.tar.gz
root/pypi flow2-6.0.0rc5.tar.gz
root/pypi flow2-6.0.0rc4.tar.gz
root/pypi flow2-6.0.0rc1.tar.gz