enable debug subpackage for coral
Merge pull request #1253 from smuzaffar/IB/CMSSW_7_3_X/gcc491

enable debug subpackage for coral
Merge remote branch 'origin/IB/CMSSW_7_3_X/gcc491' into IB/CMSSW_7_0_X/stable
Merge remote branch 'origin/IB/CMSSW_7_4_X/stable' into IB/CMSSW_7_0_X/stable