RGB image now displays correctly. New image_display button in ManualRegistrationGUI.
I have defined in ge_typedefs.h, a new PointCloud type: x,y,z,rgba,i,j
  i,j: position in RGB image of a point in the cloud.
  This will allow me to map back the planar data back to the image.

TODO: clean up interfaces. Decrease size of Register.cpp
TODO: create a group with 2 checkboxes (select which input file(s) to process).