Tweaks for combineHarveste.py
Signal model fixes:
- transfer matrix naming for correlated nuisances
- vertex deltafrac name

combineHarvester:
- automatic nuisance freeze / float
- fix parallel jobs working dir for --runLocal --parallel
Added signal model diagnostics/debug scripts
Merge pull request #415 from musella/topic_datacard_and_plots

Signal model and combineHarverster improvements/fixes