[Cython] Cython 0.26 release

[Jeroen Demeyer]

On 2017-06-21 21:51, Robert Bradshaw wrote:
> I'll see if I can put together a patch.

For what? For Sage? For Cython?

Anyway, I think that coping with this new error message is not 
particularly hard, just a lot of work. That's why I would prefer a 
warning instead of an error. That way, we can easily see how bad the 
problem is and what needs to be fixed and we fix it gradually (say, 
before Cython 0.27 which could make this a hard error).