[PATCH 2 of 2 V3] changelog: fix bug in heads computation

[Augie Fackler]

On Tue, May 26, 2015 at 3:27 PM, Laurent Charignon <lcharignon at fb.com> wrote:
> Also, we certainly want to stop using both ints and Py_ssize_t for
> revision numbers but use Py_ssize_t everywhere.
> I will send a series of patches this week to move in that direction if
> that's okay with you.

We should definitely bias towards Py_ssize_t where possible.