This change is related to the task #6397 (https://gna.org/task/?6397)
kada _at_ chemi _dot_ muni _dot_ cz
https://mail.gna.org/public/relax-devel/2010-03/msg00057.html https://gna.org/task/download.php?file_id=9686
This patch includes change of name xh_unit_vector to more general name unit_vector.
Authored by: bugman 2010-09-10
Parent: [r11540]
Child: [r11542]
