Make EvtGen to compile with gcc9
Attempt to get Gauss compiled with gcc9. In this MR I'm cleaning up EvtGen, for the rest, I will create another MR to make it easier to handle with planned remove of EvtGen sources from Gauss repository.
Attempt to get Gauss compiled with gcc9. In this MR I'm cleaning up EvtGen, for the rest, I will create another MR to make it easier to handle with planned remove of EvtGen sources from Gauss repository.