[Rivet] use of VetoedFinalState in various analyses

[Hendrik Hoeth]

Thus spake Jonathan Butterworth (jmb at hep.ucl.ac.uk):

> looks like a bug to me too. Any comments from the maintainers?

So far no comments (maintainers are Lars, Lars, Lars, and someone else).
It looks very much like a bug to me, and I've fixed it in one of the
recent revisions.

-- 
"Two equal numbers are equivalent, even if they come from two
 different people one of which you don't like"
(MLM about the theoretical top cross-section, in a meeting
about theoretical uncertainties on the top mass)