do not use cythonize() but Cython.Distutils in setup.py to avoid Cython compilation when not building the extensions

clean up extension building in setup.py: clarify what's Py3.2-specific and use cythonize() instead of Cython.Distutils

* Add Python 3.5 to the build matrix
* Rework helper build script (copied from mpi4py)

guess longness suffix of negative decimal integer literals based on their type to prevent the C compiler from truncating their value range

Though this path is never taken for unsigned ints, MSVC still throws
warning C4146.

explicitly handle CloneNode in replacement transforms to make sure we take care of its content argument

Conflicts:
	tests/run/iterdict.pyx

Fixes http://trac.cython.org/ticket/864.

--HG--
extra : amend_source : d2a97da4f942d555723b9bfa488985c5e5c27721

explicitly cast digits during PyLong conversion to avoid relying on potentially unsafe C coercion (fixes ticket #865)