PhysSelPython: few improvements for Selection framework
- Wrappers.py
- add new PayloadSelection: "pseudo-selection" where some "extra" payload algorithm is embedded into the flow. (with possible ignoring of algorithm decision)
- reimplement MomentumScaling in terms of PayloadSelection
- add special treatment of "MCTools"/"MCToolList" keyword arguments for TupleSelection: these arguments are not delegated to DecayTreeTople, instead TupleToolMCTruth is added to DecayTreeTuple and these arguments are propagated to this tool