[PyWX] Recent changes.

[Titus B. <ti...@ca...>]

Hi all,

I've spent the last few days tracking down and killing off a few problems.

In particular, the AOLbuffer code was broken with respect to threading;
since this is the fifth or sixth time that I've had to go through and
fix problems in AOLbuffer, I've ripped out the entire streambuf implementation
in favor of unbuffered reading/writing.  This removed several hundred lines
of code.

The remaining code complexity has mostly to do with (a) interacting with
Python and C++, and (b) server-parsed headers.  It seems to work quite well.

I've also updated the code for the latest release of AOLserver, v3.5.0;
unfortunately, changes in Tcl mean that I've now broken PyWX with respect
to older versions of AOLserver.  I'll be fixing this over the next few
days ;).

Finally, I fixed an old bug to do with unnecessary proliferation of
callbacks; the InterpPool code registered a cleanup callback for each
interpreter, which led to hundreds of unnecessary function calls in
long-running servers.

I will fix the compilation problems for older versions and then starting
testing the code under heavy concurrency over the next few weeks.  At
this point I have several production servers that run PyWX, so we'll find
out fairly quickly if it's stable ;).

cheers,
--titus