Fix for calling back_calc_r2eff with the new argument keywords, and use list of spin and spind ids.
Bug #22754 (https://gna.org/bugs/index.php?22754): The minimise.calculate() does not calculate chi2 value for clustered residues.
Authored by: tlinnet 2014-10-06
Parent: [r26155]
Child: [r26157]
