Moved the data filling of special numpy array errors and values, to initialization of Dispersion class.
These values does not change, and can safely be stored outside.
Task #7807 (https://gna.org/task/index.php?7807): Speed-up of dispersion models for Clustered analysis.
Authored by: tlinnet 2014-06-08
Parent: [r23746]
Child: [r23748]
