Feature/calib and sel

[mafrahm]

• adds FatJet calibrator
• implements switch between MET and PuppiMET (and uses PuppiMET in Run 3 from now on) and also propagates JEC to correct MET column
• adds nonisolated electron triggers (thanks to @BalduinLetzer for figuring out what we need)

I also added the trigger_weights producer file by accident; this is still unfinished, but should also not be a problem as long as it is not used anywhere else