Bug fix for an incorrect print statement in the N_state_model.test_paramag_centre_fit system test.
This is in the script, and was uncovered using WinPython by Troels E. Linnet
(http://gna.org/users/tlinnet) via the relax system tests at
http://thread.gmane.org/gmane.science.nmr.relax.devel/3863. The Python bug was detailed at
http://thread.gmane.org/gmane.science.nmr.relax.devel/3863/focus=3867.
