Remove vtkImageMapToWindowLevelColors color modulation
The color modulation code in this class is not used in any VTK tests or examples and appears to be cut-and-pasted from the vtkImageMapper class. Wherever vtkImageMapToWindowLevelColors is used, it appears to be used simply to apply a greyscale color mapping operation.
This commit changes the class so that color data is simply passed through.
Edited by David Gobbi