tauRecTools: move TauPi0ClusterScaler to src
There are some errors related to the ElementLink when compiling TauPi0ClusterScaler in AnalysisBase. Since we do not use this tool in AnalysisBase, it is moved to src.
There are some errors related to the ElementLink when compiling TauPi0ClusterScaler in AnalysisBase. Since we do not use this tool in AnalysisBase, it is moved to src.