Convert Py_ssize_t using PyInt_FromSsize_t

Py_SAFE_DOWNCAST can evaluate its first argument multiple
times in a debug build.  This caused two distinct assert-
failures in test_unicode run under a debug build.  Rewrote
the code in trivial ways so that multiple evaluation of the
first argument doesn't hurt.

mixing signed and unsigned types in comparison.
Relatedly, `dataSize` is declared as DWORD, not as
int, so change relevant cast from (int) to (DWORD).

whitespace.

signed with unsigned types in comparison.

test_file to fail on Windows in reality (can't delete
a still-open file), but a new bare "except:" hid that
test_file failed on Windows, and leaving behind the
still-open TESTFN caused a cascade of bogus failures
in later tests.

So, close the file, and stop hiding failure to unlink.

* Allow the 3rd argument to generator.throw() to be None.
  The 'raise' statement does the same, and anyway it follows the
  general policy that optional arguments of built-ins should, when
  reasonable, have a default value specifiable from Python.

Support 2.4 (released versions) better.  (rsync was not working with adding the *.  Only some files/dirs were copied, not everything.)

readline/readlines/read/readinto, loudly break by raising ValueError, rather
than silently deliver data out of order or hitting EOF prematurely.

Probably not a bugfix candidate, even though it affects no 'working' code.

http://mail.python.org/pipermail/python-dev/2006-February/060524.html

Proposed by Tim Peters.

call_function(), rather than commenting on the lack of an explanation in a
comment.