fix leak in DataObject
allow use of InteractorStyleImage with arbitrary data
implement data specific rendering functions using Strategies
use vtkEventQtSlotConnect instead of vtkCallbackCommand subclass in RendererConfigWidget
add RenderViewStrategie3D
fix events and memory leak in RenderView
extend/implement 2D/3D rendering strategies
fix strategy activation/deactivation
prepare RenderViewStrategyImage2D to create profile plots
edit loaded file list only via DataSetHandler
basic line plot support
clean up RenderedImageData
use processedDataSet to determine DataObject's bounds
tweak axes/labels