Release Gauss v54r2 for Sim10

This release has some bug fixes or minor new feature with respect to v54r1

It includes:

!570 (merged) Possibility to produce IFT samples with Pythia8+Argantyr
!561 (merged) Access to Polarisation for spin 1/2 baryons
!595 (merged) Algorithm for in depth tests of EvtGen
!589 (merged) Change of default PDF for SuperChic2
!578 (merged) RootInTES fix for GenSFR
!567 (merged) New Hidden Valley particle in G4
!600 (merged) Bug fix for rare looping events in EvtGen

Edited May 13, 2020 by Gloria Corti