1) KoSelection is completely refactored. Now it is always *recursive*.
   More than that, now it automatically tracks the transformation changes
   of the containing shapes (using KoShape::ShapeChangeListener)

2) The size of KoSelection is now automatically tracked as well.

3) A lot of small fixes in DefaultTool transformation strategies. Now
   you can easily transform everything: single shapes, multiple
   selections and groups.

There is still one bug: scaling of multi-object selection works weirdly.