LOAD RGB IMAGE
Macro: I_OLIMRGB
Function: To load colour image (data in bytes), where each point has its three contiguous components (R,G,B) with different parameters.
Parameters:
1. Info on image
-- number of bytes in header
-- number of lines 
-- number of byte triplets per line 
-- number of triplets <RGB> per line 
-- nbs: not used.
2. Image planes on which to load R, G, and B components of the file. 
