Backport of the GenHFHadronMacther from CMSSW_7_X

Tool for finding b/c hadrons at generator level, matching them to gen. jets and finding origin b/c quark to distinguish between e.g b hadrons coming from top quark, Higgs boson, Z boson, gluon etc.
The tool works with Pythia, Herwig, Sherpa.
Protected against infinite particle loops.