gerbaudo/SusyNtuple — pull request #7 by gerbaudo (2014-04-26 06:34:56+00:00)
Title: implement determineParentPdg

Implement `WhTruthExtractor::determineParentPdg`: navigates
the truth table and determines the pdg of the parent particle.
We are storing only one parent pdg; this is fine most of the times,
but in principle a particle can have multiple parents, so in that case
we just pick the first one.