Author: Christian Fufezan

  This script will calculate the displacement between each atom of 
  two different but aligned structures, actually chains. 
  The maximal difference will then be mapped to the alpha carbon so 
  an easier visualization via the backbone illustration is possible.
  The syntax for the script is "colordisplace chain start end shift".
  Chain defines (obviously) the chain, start and end the start and 
  end residue to be compared. The shift can be used if the numbering 
  between the two chains is different (e.g. chain E is shifted by 1 
  aminoacid in the 1S5L structure compared to the 2AXT structure, 
  therefore the syntax would be "colordisplacement E 8 84 -1"). 
  If the structures can not be compared e.g. if an aminoacid is 
  missing some atoms and therefore the amount of atoms between the 
  aminoacids to be compared are different, it will print the 
  corrosponding residue number.