CaloCellEnergyRescaler and CaloCellTimeCorrTool: Migrate to CondHandles
Migrate the two calo-cell correction tools CaloCellEnergyRescaler and CaloCellTimeCorrTool to CondReadHandles.
Move the initialization of the CaloCondBlobFlt object from an IOV-callback method into the process method of the tool, eg do it on every event. The CaloCondBlobFlt is a light wrapper around the AttributeList, the performance penalty of re-creating it on every event seems to be negligible (not visible on 25 events).
Change the base-class of the CaloCellTimeCorrTool from CaloCellCorrection tool to ICaloCellMaker.This means that we do the loop over CaloCells now ourselves so we can create the CaloCondBlobFlt once per event (instead of once per cell and event which would be crazy).