adjust image accordingly

   resulting coord must satisfy lo <= coord < hi

   MAX is important since coord - prd < lo can happen when coord = hi

   for triclinic, atom is converted to lamda coords (0-1) before doing remap

   for triclinic, point is converted to lamda coords (0-1) before doing remap

   image = 10 bits for each dimension

   increment/decrement in wrap-around fashion

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