Change "Py_intptr_t" declaration in numpy.pxd to what CPython uses as...

Change "Py_intptr_t" declaration in numpy.pxd to what CPython uses as fallback. "int" seems overly lazy if it tends to be larger on many systems.

Cython/Includes/numpy/__init__.pxd

@@ -21,7 +21,7 @@ cdef extern from *:
 
 
 cdef extern from "Python.h":
-    ctypedef int Py_intptr_t
+    ctypedef Py_ssize_t Py_intptr_t
 
 cdef extern from "numpy/arrayobject.h":
     ctypedef Py_intptr_t npy_intp