Bernsten ref now has p0 fixed to 1e-6
Merge branch 'master' into bernFixAParam

Merging in fix to chi^2 calculation when params are fixed
in RooModelPlotter
Added code to save data and fit curves in RooModelPlotter

  also added singleUseScripts/comparePullPlots.py to compare them
bkgPlotter.py now shows diff between fits

  through improved RooCompareModels
bkgPlotter.py: pull hist comparisons
Merge branch 'master' into bernFixAParam

  merge in updated fitBiasStudy.py debugging
  output into bernFixAParam
Merge branch 'master' into fitChecks

  update with fixing of Bernstein param
  and bkg comparison plots