[Python-3000] PEP 3121 implemented

[Stefan Behnel]

Hi Martin,

Stefan Behnel wrote:
>> Martin v. Löwis wrote:
>>> I just finished a PEP 3121 implementation
> 
> what's the migration path to write portable code, then?

Looking through your complete commit, I realised that it's actually not that
hard to work around the API changes by basically providing a dummy PyModuleDef
with the original Py_InitModule4() parameters, which I now did in Cython.

Just to mention it, I actually like the new API a lot, and we'll build upon
that to provide better module cleanup support in later versions. That's
something that we were missing for a while already.

Thanks,
Stefan