Fix for only multiplying with an even number of the minimum CPMG frequency.
bug #22008: (https://gna.org/bugs/index.php?22008) Interpolation with relax.plot_disp_curves, creates un-even number of CPMG blocks.
This makes sure that only an even power of NCYC blocks are created.
Authored by: tlinnet 2014-05-03
Parent: [r22936]
Child: [r22938]
