Visualization state problem (16.12.08)
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A view on profile data should use its own visualization state, such
as currently selected/activated item, attributes such as
absolute/percentage and so on.
A view can be console output, a toplevel window (we want to support
multiple for the same data!), or even subviews inside of a view
(different cost item activations (REALLY NEEDED)).

Currently, this visualization state is stored either
* in the single Configuration object
* attribute of toplevel windows (eg. options from tool bar)

Problems:
* Which configuration options persistent between runs of the app?

Todo:
* Use separate VisualizationState objects
