Fix ParticleVertexFitter in charm/cbaryon_to_ph0_btag.py
The ParticleVertexFitter in
will try to combine the proton from the Lc+ and the pion from the Lb into a single vertex, hence selecting only Lc mesons with flight distance compatible with zero, while the desired behaviour is probably different. ParticleAdder probably wouldn't solve the problem due to huge combinatorics. This looks like a good place to use DecayTreeFitter (to be tested). Otherwise, the trigger line should probably be removed.