1/ getargs.diff adds the 'Z' and 'Z#' format specifiers for
PyArg_ParseTuple. They mimic z and z# for unicode strings, by accepting
a Unicode or None (in which case the Py_UNICODE* pointer is set to
NULL). With doc and tests.

2/ subprocess.diff converts file PC/_subprocess.c to unicode. We use the
Unicode version of the win32 api (and Z conversion from previous patch)

3/ stdout.diff: sys.stdout must not convert the line endings, Windows
already does it.
Without this patch, when redirecting the output of python, the file
contains \r\r\n for each line. (test_subprocess did catch this)

However, I (GvR) removed the change to _fileio.c (included in the
patches) that prevents closing file descripors < 3 from being closed;
I think that needs to be solved in a different way.