updated storage of flavour information in pat::Jet and added ioread rule for backward compatibility
replacing the 'consumes' call for leptons by 'mayConsume'
Merge pull request #3601 from cms-btv-pog/UpdatedJetFlavourStorage_from-CMSSW_7_1_X_2014-04-29-0200

Updated storage of flavor information in pat::Jet