Added an extra slash so the user doesn't have to have one in
external_systematics_directory.
Added an option for turning off the factorization and simply using
cut-and-count to get the yields.
Added the cross section and its uncertainty for the 900 GeV stop.
Added the cross section and its uncertainty for the 900 GeV stop.
Added the cross section and uncertainty for a 1000 GeV stop.
Added the cross section and uncertainty for a 1000 GeV stop.