Switch PreMix stage 2 output to modified RAWSIM

Conflicts:
	Configuration/EventContent/python/EventContent_cff.py
Add DIGIPREMIX_S2 process Key
Add validation digi sequence invoked by cmsDriver
Hack around hack for missing CSC Raw2Digi->Digi2Raw converter

Conflicts:
	SLHCUpgradeSimulations/Configuration/python/muonCustomsPreMixing.py
	SLHCUpgradeSimulations/Configuration/python/postLS1CustomsPreMixing.py
	SimGeneral/DataMixingModule/plugins/DataMixingModule.cc
	SimGeneral/DataMixingModule/python/mixOne_simraw_on_sim_cfi.py
PreMixing - additions for validation/DQM
7_0_X Change DataMixer to merge CSC Strip Digis instead of adding duplicates
Finally...

Conflicts:
	SimCalorimetry/HcalSimAlgos/interface/HcalSignalGenerator.h
	SimCalorimetry/HcalSimAlgos/src/HcalElectronicsSim.cc
	SimCalorimetry/HcalSimAlgos/test/HcalDigitizerTest.cpp
	SimGeneral/DataMixingModule/python/mixOne_simraw_on_sim_cfi.py
catch compilation error
remove printout
7_0_X Change DataMixer to merge CSC Strip Digis instead of adding duplicates
Fix RPC noise in PreMixing

Conflicts:
	SimMuon/RPCDigitizer/src/RPCDigitizer.cc
Configure SiStrip noise the same in production and validation modes! Suppress cout in Hcal

Conflicts:
	SimCalorimetry/HcalSimAlgos/interface/HcalSignalGenerator.h
Put starting capId back to random to fix drop in number of digis in Hcal
adding new mode PREMIX_RAW for MC
All code modifications to fix saturation issues in SiStrip Tracker for PreMixing

Conflicts:
	SimTracker/SiStripDigitizer/plugins/DigiSimLinkAlgorithm.cc
	SimTracker/SiStripDigitizer/plugins/SiStripDigitizerAlgorithm.cc
Script changes to set PreMixing parameters for SiStrips