Current snapshot of work.  Nearly finished working with the plane manipulation.
Implementing working image plane manipulation.
Set up undo/redo for plane movement.
Add undo redo functionality for view change.
Updating documentation to match latest.
Adding the ability to create streaming segmentation points.  Adding functionality to show/hide various graphic elements of the tool.
Refactor to move a lot of code outside of the segmentationwidget module.
Fixing bug where the plane normal glyph was not positioned properly.
Refactoring for using a 2d view.  Changing the model to use inheritance to control the behaviour that I want.  Starting to add a draggable tab widget to modify the view.
Moving towards adding the ability to move tabs from a stacked view to a side-by-side view.
Almost developed the tab moving enough to say it is done.  Still a few niggles present.
Progress in refactoring.
Progress so far committing before launching on the next phase.
Striping the model down into constituent parts.  The model has gone from one SegmentationModel to an ImageModel and NodeModel to better encapsulate the underlying abstract models in use.
Progress towards getting it working again after this refactor.
Added the sceneviewer3d to the construction of the sceneviewer2d so that they can share opengl contexts.  I have had to edit the ui_segmentationwidget.py by hand to make this possible so be aware when generating with pyside-uic that it will need to be put back in place otherwise nothing will show up on the 2D sceneviewer widget.
Getting the rotation mode working and updating the 2D image plane view.
Changing the _notifyChange method to notifyChange which now does nothing.
Changed the view mode glyphs to use the field coordinate for position instead of the glyph relative attributes.  Moved the centroid algorithm out of the plane class into algorithms.
Remove dimensions from Plane object.