Electron multi threading

New DQM validation migration to multithread & histos modifcations

It involves the following packages:

DQMOffline/EGamma
DQMOffline/EGamma/interface/ElectronDqmAnalyzerBase.h
DQMOffline/EGamma/interface/ElectronDqmHarvesterBase.h
DQMOffline/EGamma/src/ElectronDqmAnalyzerBase.cc
DQMOffline/EGamma/src/ElectronDqmHarvesterBase.cc

Validation/RecoEgamma
Validation/RecoEgamma/plugins/ElectronMcFakePostValidator.cc
Validation/RecoEgamma/plugins/ElectronMcFakePostValidator.h
Validation/RecoEgamma/plugins/ElectronMcFakeValidator.cc
Validation/RecoEgamma/plugins/ElectronMcFakeValidator.h
Validation/RecoEgamma/plugins/ElectronMcSignalPostValidator.cc
Validation/RecoEgamma/plugins/ElectronMcSignalPostValidator.h
Validation/RecoEgamma/plugins/ElectronMcSignalValidator.cc
Validation/RecoEgamma/plugins/ElectronMcSignalValidator.h
Validation/RecoEgamma/python/ElectronMcFakePostValidator_cfi.py
Validation/RecoEgamma/python/ElectronMcFakeValidator_cfi.py
Validation/RecoEgamma/python/ElectronMcFakeValidator_gedGsfElectrons_cfi.py
Validation/RecoEgamma/python/ElectronMcSignalPostValidator_cfi.py
Validation/RecoEgamma/python/ElectronMcSignalPt1000Validator_cfi.py
Validation/RecoEgamma/python/ElectronMcSignalPt1000Validator_gedGsfElectrons_cfi.py
Validation/RecoEgamma/python/ElectronMcSignalValidator_cfi.py
Validation/RecoEgamma/python/ElectronMcSignalValidator_gedGsfElectrons_cfi.py

python files are modified to take into account the setEfficiencyFlag and the StatOverflowFlag