WIP commit
The BrushCreatorTool seems to work, it's all a bit rough, still.
Some refactoring.
WIP commit (clipper)
Most functionality is in ClipperTool now, lots of refactoring possible.

Also need to implement passing mouseMove events to passive tools.
More WIP code to get mouse move events to all tools that want them anyway.
More sophisticated return type.
WIP commit, add support for pointer capture.
ZoomTool implementation done.
Update docs, disable old code.
Reorganise tool implementation files into separate folder.
Implement CameraAngleTool.
Implement CameraMoveTool.
Implement MoveViewTool and factor out the context menu handling.
First round of cleanup.
XYWnd: #include cleanup and naming conventions.
Enable chasemouse behaviour for all tools. Plus some refactoring.
Rename context menu related member variables.
Move headers to include/ folder.
WIP commit, defining view interfaces needed for selection tests.