remove vertex chi2dof cut from d0-to-hhpi0 lines
As discussed in #940 (closed) , a vertex chi2/ndof selection doesn't make sense when combining two neutral particles.
In the latest software stack, doing so makes this combination fail the CompositeCut.
Possibly it would make sense to use ParticleAdder for the combination instead.
addresses #940 (closed)
cc @totodoro
Edited by Flo Reiss