Adding SUSY20 derivation format

SUSY20 derivation format is needed by compressed SUSY analyses aiming to exploit both Run-2 and Run-3 data. The format is obtained by upgrading the one already existing in R21 and makes use of a tool that will be added by the linked merge request (currently pending). Code lines in the python scripts that are commented out refer to variables/tools not needed for the moment but that will be restored once all compressed SUSY analyses will join the effort in R24.

Tagging also @tlari