Tag to be used with the master branch of atlas/athena. Update(s) since 2.0.129: - Updated histgrinder to version 0.1.5; - Updated CLHEP to version CLHEP_2_4_1_3_atl03; - Removed VecGeom from AthenaExternals and AthSimulationExternals, and stopped Geant4 from using it.