Fix color scalarbar
Created by: mehrtash
ENH: Fixed color scalar bar by replacing vtkScalarBaractor with vtkPVScalarBarActor
Improvements:
- Color scalar bar was enhanced and the bugs were fixed by adding Paraview vtkPVScalarBarActor to module's logic
- Replaced vtkScalarBarActor with vtkPVScalarBarActor
- Made the logic sensitive to dicom volume. (for none dicom volumes the color scalar bar would occupy 100% of the view's width)
- Change the format of foreground volume and label opacities to percentage (e.g. from 0.4 to 40%)