[PWGCF] FemtoUniverse: PID selection update, corr. bkg histos for D0

[kgwizdzi]

femtoUniverseEfficiencyBase.cxx changes:

• adding the possibility to force TOF information for tracks, so if a track doesn't have a TOF information it is rejected - configurable forceTof (Note: for processes with V0 should be set to 0 in order to avoid bad PID selection for V0 daughters)
• adding the possibility to verify if the track has TOF information and then do the PID selection accordingly, what means that, if a track has TPC and TOF information then it is selected based on both nSigma values from a given momentum threshold, but if TOF information is missing then it is selected based on the TPC nSigma value only - configurable checkIfTofAvailable (Note: for processes with V0 should be set to 0 in order to avoid bad PID selection for V0 daughters)
• if checkIfTofAvailable set to 0, then for tracks with a momentum above a given momentum threshold, tracks without TOF information will be rejected (it does the selection as it was done so far)
• all the functions for PID selection and rejection have a new variable partHasTof, which provides information if a track has TOF
• std::hypot() changed to std::sqrt(std::pow(,2)+std::pow(,2))

femtoUniversePairTaskTrackD0.cxx changes:

• new configurable fillCorrBkgs - enable if histograms with correlated background for D0/D0bar candidates should be filled
• histograms for D0/D0bar candidates from the correlated background added