Add option to add new color maps for overlay

[sarthakpati]

Is your feature request related to a problem? Please describe.
Currently, there is no option for changing the colormap, and adding this option would be nice.

Describe the solution you'd like
Add option to change colormap for better visualization.

Describe alternatives you've considered
N.A.

Additional context

• Look-up table is ready: https://github.com/CBICA/FigureGenerator/blob/main/FigureGenerator/utils.py#L5
• The following option in utils.alpha_blend did not work:

  filter_overlay.SetColormap(sitk.ScalarToRGBColormapImageFilter.Jet)