loosen lhe header compatibility check given that random seeds and number of events may change from job to job for madevent and madspin
remove no-long-working workaround for amcatnlo event weights
add run script for amcatnlo tarballs
Merge pull request #2689 from bendavid/amcatnloprod

Generator fixes -- Changes to allow aMC@NLO production with ExternalLHEProducer