Add EvtBcVPPHad model for Bc to Jpsi p pbar pi decays and generalise the particle ordering
for EvtBcVHad decay files, courtesy of Aleksei Luchinsky, Dmitrii Pereima & Vanya Belyaev (LHCb).
Updated EvtPhiDalitz model to use helicity amplitudes and fixed the indices used in the
EvtVector3R::dot() function, courtesy of Arnau Brossa Gonzalo & Antonio Romero Vidal (LHCb).