The new QmitkAbstractMultiWidget(Editor) serves as a base class for the two multi widgets (editors): `QmitkStdMultiWidget(Editor)` and `MxNMultiWidget(Editor)`
In order to make both variants work all occurrences of the `StdMultiWidget(Editor)` have to be checked and potentially replaced with a `QmitkAbstractMultiWidget(Editor)`.
Candidates are
[x] ~~`QmitkAdaptiveRegionGrowingToolGUI`~~
[x] `QmitkPointListWidget`
[x] ~~`QmitkPointListViewWidget`~~ --> removed in T26547 / D661
[x] `QmitkPointListView`
[x] `QmitkFiducialRegistrationWidget`
[x] `QmitkIGTTrackingDataEvaluationView` and `QmitkIGTTrackingSemiAutomaticMeasurementView` (has been fixed with {D666})
- ~~still dependent on `QmitkFunctionality` (see {T29200})~~
[] `QmitkUSNavigationMarkerPlacement`
- seems to do some special layouting with the StdMultiWidget(Editor)
Additionally some StdMultiWidget includes / forward declarations are unnecessary.