move SpreadEstimator, SharedCells, Digit2ClusterConnector from LHCb to CaloFutureReco

Gerhard Ravenrequested to merge
move-covariance-estimator into master

move SpreadEstimator, SharedCells, Digit2ClusterConnector from LHCb to CaloFutureReco

Edited by Gerhard Raven

Merge request reports