message: EMCal CorrFW: Update docs
  Added notes about the use of `CDBconnect`
diff: @@ -18,6 +18,7 @@ The following correction components are available:
  - [CellBadChannel](\ref AliEmcalCorrectionCellBadChannel) -- Sets cells marked as bad to E = 0, using OADB bad channel map.
  - [CellEnergy](\ref AliEmcalCorrectionCellEnergy) -- Performs energy calibration of cells, using OADB calibration.
  - [CellTimeCalib](\ref AliEmcalCorrectionCellTimeCalib) -- Performs time calibration of cells, using OADB calibration.
  +- [EmulateCrosstalk](\ref AliEmcalCorrectionCellEmulateCrosstalk) -- Emulate cell-level crosstalk.
  - [Clusterizer](\ref AliEmcalCorrectionClusterizer) -- Clusterizes a collection of cells into a collection of clusters.
  - [ClusterExotics](\ref AliEmcalCorrectionClusterExotics) -- Flags exotic clusters for removal from the cluster collection.
  - [ClusterNonLinearity](\ref AliEmcalCorrectionClusterNonLinearity) -- Corrects cluster energy for non-linear response.
  @@ -69,6 +70,8 @@ correctionTask->SetUserConfigurationFilename("userConfiguration.yaml");
  correctionTask->Initialize();
  ~~~
  +Note that this should be added after `CDBconnect`, which is required to use the correction framework.
  +
  ## LEGO Train Wagon {#emcCorrectionsLEGOTrainWagon}
  There are some special procedures for the LEGO train. There will be a centralized EMCal Correction Task wagon which
  @@ -472,6 +475,23 @@ for (int i = 0; i < clusters->GetEntries(); i++) {
  }
  ~~~
  +# FAQ {#emcCorrectionsFAQ}
  +
  +## I am seeing an error related to the EMCal geometry - what is wrong? {#emcCorrectionsGeometryError}
  +
  +For example, you may see an error similar to below.
  +
  +~~~
  +F-AliEMCALGeometry::GetMatrixForSuperModule: Cannot find EMCAL misalignment matrices! Recover them either:
  +- importing TGeoManager from file geometry.root or
  +- from OADB in file OADB/EMCAL/EMCALlocal2master.root or
  +- from OCDB in directory OCDB/EMCAL/Align/Data/ or
  +- from AliESDs (not in AliAOD) via AliESDRun::GetEMCALMatrix(Int_t superModIndex).
  +Store them via AliEMCALGeometry::SetMisalMatrix(Int_t superModIndex)
  +~~~
  +
  +This is due to the OCDB being unavailable. Please ensure that you ran the `CDBconnet` task.
  +
  # Details on the framework and the corrections
  You can see the code at ``$ALICE_PHYSICS/PWG/EMCAL/EMCALtasks``. The steering class is ``AliEmcalCorrectionTask``. The
  