Migration of ISF_HepMC_Tools to HepmC3
In this MR:
- Migration of ISF_HepMC_Tools to HepmC3 The main change is the switch from pass by reference to pass by value because of smart pointers.
Tip for the reviewers: all no code is removed and all the added codes are behind #ifdef HEPMC3.
Edited by Andrii Verbytskyi