biasStudy: measure bias in mu & can do signal inject

  signal injection in terms of mu
  non of the labels have been set up for
    signal injection or mu
fitBiasStudy.py: mu combination & deleted some plotting functionality
fitBiasStudy.py: set options to sensible defaults
Merge pull request #5 from jhugon/biasWithSignalInject

Merge in Bias with signal inject