Cherry-pick of "Merge branch 'EnableDMTCPForAthDerivation-1.0-20170620' into '1.0'" into master
Add DMTCP to AthDerivationExternals, 1.0 branch (2017.06.20.)
See merge request !73 (merged)
Add DMTCP to AthDerivationExternals, 1.0 branch (2017.06.20.)
See merge request !73 (merged)