py-cffi: updated to 1.11.5

v1.11.5

* Issue 357_: fix ffi.emit_python_code() which generated a buggy
  Python file if you are using a struct with an anonymous union
  field or vice-versa.

* Windows: ffi.dlopen() should now handle unicode filenames.

* ABI mode: implemented ffi.dlclose() for the in-line case (it used
  to be present only in the out-of-line case).

* Fixed a corner case for setup.py install --record=xx --root=yy
  with an out-of-line ABI module.  Also fixed Issue 345_.

* More hacks on Windows for running CFFI's own setup.py.

* Issue 358_: in embedding, to protect against (the rare case of)
  Python initialization from several threads in parallel, we have to use
  a spin-lock.  On CPython 3 it is worse because it might spin-lock for
  a long time (execution of Py_InitializeEx()).  Sadly, recent
  changes to CPython make that solution needed on CPython 2 too.

* CPython 3 on Windows: we no longer compile with Py_LIMITED_API
  by default because such modules cannot be used with virtualenv.
  Issue 350_ mentions a workaround if you still want that and are not
  concerned about virtualenv: pass a define_macros=[("Py_LIMITED_API",
  None)] to the ffibuilder.set_source() call.

(adam)