TopQuarkAnalysis/TopSkimming: add missing dependency on DataFormats/Common

Signed-off-by: David Abdurachmanov <David.Abdurachmanov@cern.ch>
Merge pull request #2470 from davidlt/add-missing-dep-on-DataFormats-Common

TopQuarkAnalysis/TopSkimming: add missing dependency on DataFormats/Common
Merge remote branch 'origin/CMSSW_7_1_X' into CMSSW_7_0_X