Add a Zero material scenario based on 2015 Extended one
Add missing material
Payload producer for Zero material scenario
Zero material scenario for Extended 2015
Fix density to zero
Merge pull request #5109 from ianna/zero-material-scenario-2015

Zero Material Scenario 2015
Merge remote branch 'origin/CMSSW_7_2_X' into CMSSW_7_0_X