Log Message:
py-cffi: updated to 1.17.1

v1.17.1

* Fix failing ``distutils.msvc9compiler`` imports under Windows
* ``ffibuilder.emit_python_code()`` and ``ffibuiler.emit_c_code()`` accept \ 
file-like objects
* ``ffiplatform`` calls are bypassed by ``ffibuilder.emit_python_code()`` and \ 
``ffibuilder.emit_c_code()``