#29 Build failure when scons uses python 3 (patch attached)

[Ryan Carsten Schmidt]

gmtl 0.6.1 doesn't build when scons is using python 3.10.

This was reported to MacPorts here: https://trac.macports.org/ticket/67067

I used the 2to3 script along with some changes I made manually to arrive at the patch I'm attaching to this ticket.

The one remaining issue is the use of popen3. I attached a patch to fix that here: https://sourceforge.net/p/ggt/bugs/28/#b0a5

I'm not a python expert so there may be better ways to fix some of these things.