update cmssw plots, add ttbar sample to valid, add multiparticlegun and vbf to training

[jpata]

• update training samples to include high-stats VBF and multi-particle gun
• add ttbar to CMSSW validation samples
• update CMSSW plotting notebook
• removed DQM from validation jobs as it seemed to crash with some CSCDigiValidation:cscDigiValidation errors. Doing the validation manually on top of MINIAOD now using notebooks/cms/cmssw.ipynb
• disable Ray test for now due to #331
• latest CMSSW validation here: https://indico.cern.ch/event/1426959/#2-cms-status-and-plans