Split the MuonTruthDecorationAlg into four smaller algorithms.

I split the MuonTruthDecorationAlg into four smaller algorithms, in order to decrease the complexity and allow running a subset of decoration algorithms. Conceptually, the implementation and workflow are the same of the old algorithm, with a few minor changes. The most relevant one is the utilization of StoreGate/Decorators instead of AthContainers/Decorators.