Fix issue #9711: raise ValueError is SSLConnection constructor is invoked with keyfile and not certfile.

Sébastien Sablé.

in ssl tests rely on IOError.errno rather thanf IOError.strerror for better compatibility across platforms.

Raise ValuError if non-zero flag argument is provided for sendall() method for conformity with send(), recv() and recv_into()

to the socket module, and fix the width of socket descriptors to be
correctly detected under 64-bit Windows.

getting rid of the cached copy of thread-local attribute dictionary.

inputs to the nearest integer.  Thanks Neil Tallim for the patch.

and make.

already exists, not IOError.

Part of the continuing saga of issue #9572.

LC_ALL is read before LANG to choose the locale encoding (LC_ALL, LANG and then
LC_CTYPE: use the first non empty variable).

Two character years are now converted to four character years using
the Posix standard rule (<68 == 2000, >=68==1900).  This makes the
parsed date RFC2822 compliant even if the input is not.

Patch and test by Jeffrey Finkelstein.

This test is irrevelant on Windows

_Py_char2wchar() (mbctowcs) decodes b'\xff' to '\xff' on FreeBSD, Solaris and
Mac OS X, even if the locale is C (and the locale encoding is ASCII). Patch
test_undecodable_code() to support this output and document the two different
kinds of outputs.