Enable ColorizeVolume to work with already existing RGB volume #28
Description
I have saved the color volume output from the ColorizeVolume to disk. However, I still have to load the original intensity image and the segmentation, next time when I need to work on in Slicer. It would be nice to have load data from scene/disk option. I like the controls in ColorizeVolume better than the VR ones, so would like to keep using them.