new jet flavour definition
- migration to the consumes interface to make the code thread-safe

- minor code updates to make it work in 7_1_X (originally developed in 5_3_X)
minor tweaks to the config files
made PhysicsTools/JetExamples/test/printGenJetRatio.py functional again
updated handling of flavour conflicts
updated definition of parton-based jet flavour
added Sherpa to the list of supported generators
added Herwig++ to the list of supported generators
clustered "ghost" particles now ordered by Pt
expanded description of hadron selection
improved handling of jet Pt mismatches
updated warning messages
switching to status=71 partons in Pythia8 which are equivalent to status=2 partons in Pythia6
general code cleanup and optimization, switched to using signed parton flavour codes
added "ghost" leptons
now also including c hadrons from b hadron decays
added a few documentation lines
fixed parton selectors to work correctly also with pruned GenParticles, also added status=72 partons for Pythia8
minor fix in the example code printout
included additional constructors for the JetFlavourInfo class