Little hack: do not include the theory prediction errors in case we
are running on the HAD_UP/DOWN samples (POWHEG and MCATNLO)
Add updated tool for closure plot combination. This tool now uses
the plotter utils from topmassextractor. These changes have to be
ported to the other tools (or even better: unify them!)
Add gitignore ignoring evenrything except the root macro and itself.