 is wrapping the functionality of the <tt>ROOT::Math::Fitter</tt> and it
     can be used to retrieve the fit information (result and
     configuration) via the
     TVirtualFitter API from <tt>FitConfig</tt> and <tt>FitResult</tt>. A static instance of this class
     is created after calling the histograms and graph Fit methods in order to retrieve the full fit information after having fit. This instace will be deleted only when the next fit is executed.
  This gives full backward compatibility functiona