message: PWG/EMCAL: Add Low energy efficiency correction to readme document
diff: @@ -23,6 +23,7 @@ The following correction components are available:
  - [ClusterExotics](\ref AliEmcalCorrectionClusterExotics) -- Flags exotic clusters for removal from the cluster collection.
  - [ClusterNonLinearity](\ref AliEmcalCorrectionClusterNonLinearity) -- Corrects cluster energy for non-linear response.
  - [ClusterNonLinearityMCAfterburner](\ref AliEmcalCorrectionClusterNonLinearityMCAfterburner.h) -- This is an additional correction for MC. The effect is that the pi0 mass position is the same for data and MC. It is only defined for specific periods.
  +- [ClusterLowEnergyEfficiency](\ref AliEmcalCorrectionClusterLowEnergyEfficiency.h) -- Corrects the fraction of 1 cell clusters in MC to match the data distribution. The correction will flag a percentage of the MC 1 cell clusters such that they can be used as if they have 2 cells
  - [ClusterTrackMatcher](\ref AliEmcalCorrectionClusterTrackMatcher) -- Matches each track to a single cluster, if they are in close enough proximity.
  - [ClusterHadronicCorrection](\ref AliEmcalCorrectionClusterHadronicCorrection) -- For clusters that have one or more matched tracks, reduces the cluster energy in order to avoid overestimating the particle's energy.
  - [PHOSCorrection](\ref AliEmcalCorrectionPHOSCorrections) -- Perform PHOS correction via an interface to the PHOS tender.
  