Add an option (default off) to map and unmap workspaces in the "best"
order when switching workspaces.
The best order is to first unmap back-to-front (this avoid exposures of
parts of hidden windows), then map front-to-back (which prevents that
a just-mapped window gets partially hidden again).
Enable this code with

SwitchWorkspacesOrdered	1

in your .ctwmrc. If this option turns out to be ok (possibly after
improvement, it can be turned on by default. One possible improvement
would be if it were possible to keep track of the stacking order
without explicitly asking the X server with XQueryTree().
3 - Selected a number of cleanups from Stefan Monnier
<monnier@IRO.UMontreal.CA>, including rate-limiting of animations using
a new _XA_WM_END_OF_ANIMATION message.  Added some similar changes,
improved the prevention of placing windows off-screen, the
"f.rescuewindows" function for emergencies, a hack-fix for
f.adoptwindow. More virtual screen tweaks/fixes.