Optimization in Games
Replace the tabwindow interface by a standard XMLGUI window.
While the tabwindow interface had its time and justification, the new
solution is simpler and more consistent. It will make it easier to do
some more widget reordering, and add new interface components to the
Intensive testing indicates that this change has not caused any
regressions. In fact, I've applied some polish here and there,
although there are still some pieces (esp. the "Restart" and "Back to
collection" actions) which do not fit in at the moment, but I promise
that these will fall into place shortly.