Moved the bulk operation of model CPMG 2site 3d into the lib file.
This is to keep the API clean.
Task #7807 (https://gna.org/task/index.php?7807): Speed-up of dispersion models for Clustered analysis.
Authored by: tlinnet 2014-06-15
Parent: [r23956]
Child: [r23958]
