Further updates of McEventCollection codes
In this MR, for HepMC3 branch:
- Modify functions so the particles are added to vertices before manipulations with their attributes. Used only in HepMC3 branch.
- Modify functions so the vertices are added to events before manipulations with their attributes. Used only in HepMC3 branch.
- Fix status() for vertices
- Some formating.
Tag @jchapman
Edited by Andrii Verbytskyi