AntikT algorithm for Phase II GEP
This MR has the simulation of the AntikT algorithm as it is planned for the Phase II GEP and described here https://indico.cern.ch/event/1009264/contributions/4235178/attachments/2225550/3769910/Anti_kT_Status_04-13-2021.pdf
Tagging @mmazza who may be interested in following this MR.