Volume colorMIP

Enables maximum intensity projection (MIP) renderings of RGB volumes (N x M x O x 3) using volshow. The volume is broken into separate RGB components, MIP's are computed, and the result is combined. A viewpoint manipulation window containing a patch-object enables the user to change the orientation of the view.

Notes:
- This is only an approximation. A true MIP would define maxima using a luminosity measure. It is a fairly common approximation, however, and works fairly well.

- Set the popout boolean to true, to decouple the RGB image from the volshow panels.