McParticleTools: Process particles in barcode order in TruthParticleCnvTool.
In TruthParticleCnvTool, sort the GenParticles and process them in barcode order if we're using HepMC3, in order to preserve the behavior we had with HepMC2.
In TruthParticleCnvTool, sort the GenParticles and process them in barcode order if we're using HepMC3, in order to preserve the behavior we had with HepMC2.