Imported return_param_key_from_data to be used in unit test return_offset_data.
Regarding sr #3124, (https://gna.org/support/index.php?3124) - Grace graphs production for R1rho analysis with R2_eff as function of Omega_eff.
Authored by: tlinnet 2014-03-06
Parent: [r22415]
Child: [r22417]
