Update of Truth Rivet Tool
Added the Stage-1.1 and Stage-1.1-Fine versions of STXS classification: https://twiki.cern.ch/twiki/bin/view/LHCPhysics/LHCHXSWGFiducialAndSTXS#Stage_1_1 The old Stage-1 classification is not affected.
Also implemented the bugfix for ttH in the STXS classification tool spotted by RD Schaffer.
This is used in the derivation release.