varies between __main__ and other modules, and strongly suggest not touching
it but using __builtin__ if absolutely necessary

Summary of changes:

- support for 'variable sized' data
- support for anonymous structure/union fields
- fix severe bug with certain arrays or structures containing more than 256 fields

Summary of changes:

- support for 'variable sized' data
- support for anonymous structure/union fields
- fix severe bug with certain arrays or structures containing more than 256 fields

  * restore "Extending optparse" section
  * document ALWAYS_TYPED_ACTIONS (SF #1449311)

- update header checks, using autoconf
- provide dummies for getenv, environ, and GetVersion
- adjust MSC_VER check in socketmodule.c

PyThreadState_GET() complains if the tstate is NULL, but only in debug mode.

Also improve error message on overflow.

An object with __call__ as an attribute, when called, will have that attribute checked for __call__ itself, and will continue to look until it finds an object without the attribute.  This can lead to an infinite recursion.

Closes bug #532646, again.  Will be backported.

Occurences in email and compiler were ignored due to backwards compat requirements.

clean up files and directories the tests often leave behind by
mistake.  This is the first time in history I don't have a bogus
"db_home" directory after running the tests ;-)

Also worked on runtest's docstring, to say something about all the
arguments, and to document the non-obvious return values.

New functions runtest_inner() and cleanup_test_droppings() in
support of the above.

Make the definition #ARRAYSIZE conditional.  VisualStudio .NET 2005 already has it defined using a better gimmick.

[Bug #1472827] Make saxutils.XMLGenerator handle \r\n\t in attribute values by escaping them properly.   2.4 bugfix candidate.

run immediately after test_file.  At least 8 buildbot
boxes passed since the underlying problem got fixed,
and they all failed before the fix, so there's no point
to this anymore.

test clean up after itself appears to fix the test failures
when test_optparse follows test_file.

test_main():  Get rid of TESTFN no matter what.  That's
also enough to fix the mystery failures.  Doesn't hurt
to fix them twice :-)

try/except.  Remove TESTFN.

Throughout:  used open() instead of file(), and wrapped
long lines.