Code reorganization heads up

[Harold L Hunt II]

All developers,

I am pulling code out of winmultiwindowwindow.c and putting it into 
separate files that deal with more specific tasks.  This single file has 
grown to over 50 KiB, so it is time to break it apart to make it more 
manageable.  This should have been done some time ago, but, well, it wasn't.

Please try to hold off on any big patches until after tonight when I 
release a new test version.

Harold