[CC] & [RP] include DIEF@T

[TortugaAttack]

Include dief@t metric from the paper: "Diefficiency Metrics: Measuring the Continuous Efficiency of Query Processing Approaches” by Maribel Acosta, Maria-Esther Vidal, York Sure-Vetter.

A new Task has to be implement which queries the incremental time used to get all answers. This will be more of a completness check then a Stresstest though. But still use implemented techniques to assure a simple extension to a Stresstest