cmssw: set %gitcommit for DEBUG IB

Signed-off-by: David Abdurachmanov <David.Abdurachmanov@cern.ch>
Merge pull request #621 from davidlt/set-gitcommit-for-debug

cmssw: set %gitcommit for DEBUG IB
Merge remote branch 'origin/IB/CMSSW_7_1_X/stable' into IB/CMSSW_7_0_X/stable