Fix several issues relating to access to source code inside zipfiles. Initial work by Alexander Belopolsky. See Misc/NEWS in this checkin for details.

Issue #4163: Use unicode-friendly word splitting in the textwrap functions when given an unicode string.

Solaris and OpenBSD.  Fix this by handling special values and domain
errors directly in mathmodule.c, passing only positive nonspecial floats
to the system log/log10.

give correct results in the case where one argument is a quiet NaN
and the other is a finite number that requires rounding.
Thanks Mark Dickinson.

conversion to bool raises an exception, 'with' loses that exception.

Reviewed by Jeffrey Yasskin.
Already ported to 2.5, will port to 2.6 and 3.0

"raised" without setting x, err, or why to let the eval loop know.

string allocation.

It doesn't make sense for such a fundamental document to have
the most obscure function listed at the top.