WINTERMUTE: Speed up rendering

This branch aims to speed up Wintermute rendering in two ways:

* The wme_lineartickets branch merged into this one removes a bottleneck from the administration part of the ticketing system.

* It replaces repeatLastDraw by a displayTiled function, adding tiled rendering as a parameter to TransformStruct.

To ease implementation, it no longer disables dirty rects when there are too many tickets. The displayTiled change means the largest source of tickets is gone, so this behaviour should no longer be necessary.