porting upgrade features to 73X branch in digitizer
Merging of pixel digitizer (from upgrade)
Merging of pixel digitizer (from upgrade)
Merging of pixel digitizer (from upgrade)
Merge pull request #5717 from ahazi137/pdigitizer-merging-curr-upg-3

Sim -- Pdigitizer merging curr upg 3
Force rebuild.
Merge pull request #5793 from ktf/force-rebuild

Force rebuild.
Merge remote branch 'origin/CMSSW_7_3_X' into CMSSW_7_0_X