Created the 'MQ NS CPMG 2-site' model target function.
This follows the tutorial for adding relaxation dispersion models at: http://wiki.nmr-relax.com/Tutorial_for_adding_relaxation_dispersion_models_to_relax#The_target_function
Authored by: bugman 2013-10-10
Parent: [r21064]
Child: [r21066]