Add new functions to convert C ``<stdint.h>`` numbers from/to Python
:class:`int`:
* :c:func:`PyLong_FromInt32`
* :c:func:`PyLong_FromUInt32`
* :c:func:`PyLong_FromInt64`
* :c:func:`PyLong_FromUInt64`
* :c:func:`PyLong_AsInt32`
* :c:func:`PyLong_AsUInt32`
* :c:func:`PyLong_AsInt64`
* :c:func:`PyLong_AsUInt64`
Patch by Victor Stinner.