Added configuration for CMSSW_7_2_X

Also the following branches were created:

IB/CMSSW_7_2_X/stable based on IB/CMSSW_7_1_X/stable
IB/CMSSW_7_2_X/gcc490 based on IB/CMSSW_7_1_X/gcc490
IB/CMSSW_7_2_X/next based on IB/CMSSW_7_1_X/next
IB/CMSSW_7_2_X/geant10 based on IB/CMSSW_7_1_X/geant10
CMSSW_7_1_THREADED_X now uses IB/CMSSW_7_1_X/stable
Merge remote branch 'origin/IB/CMSSW_7_0_X/stable' into IB/CMSSW_7_0_X/stable