Determine and optimal number of sub-images for a large set of images to stacked with clip_stacker.sh.

 
% stack_mod.sh --help   
% stack_mod.sh List.FINAL_ISET   

Usage: stack_mod.sh List.FINAL_ISET
arg1 - list of fullpath image names for stacking
Additional options:
     -v = print verbose comments
 --help = view a help document

% stack_mod.sh List.FINAL_ISET
 7    42
  
Th output, written to standard out, is:
   nsub   = number of image in a substack 
   ntot   = yotal number of images that will be stacked