PEP 503 package name canonicalization

[kdeldycke]

PyShop doesn't seems to canonicalize package names according the PEP 503. See: https://github.com/pypa/pip/commit/8e236dd6a09bd2f70f9d4fc886da8c354d4c58f2

As a result a package mirrored by PyShop can't be install if containing a dot with pip >= 8.1.2 because of the non-canonicalized name.