New windowing code

[Takuma Murakami]

I committed a couple of changes on windowing in multiwindow
mode to the xorg CVS tree.  Here I mean move, resize,
minimize, maximize, and restore operations as 'windowing'.

This should fix the following problems about windowing.
1) Maximize->Minimize->Maximize loses the window contents.
2) After 1, window size cannot be correctly restored.
3) Left and top borders does not resize but move the window.
4) Moved window occasionally fails to update its contents.

A note for test: if you compile it from CVS, you need to do
'touch winallpriv.c' after 'cvs update' or XWin.exe crashes
on exiting.

Any comments, questions, test/bug reports will be
greatly appreciated.

Takuma Murakami