In mitk::SlicedGeometry3D::InitializeEvenlySpaced() the origin of the geometry is calculated incorrectly.

Now, if the axis is not flipped, the origin is the same as that of the plane geometry used for the initialisation. However, it should be shifted with half spacing along the direction that is orthogonal to the plane. The same should be done if the axis is flipped, just to the opposite direction.

The bug causes that if you construct three sliced geometries, one for each renderer, then the bounding box of these geometries will not be the same, nor the centre, origin or corner points. These should all be equal.