- In case the errors of the fit parameters had large values (>E+07)

  the fit result in the stat box looed not very nice. 
  The Method GetBestFormat have been changed. The problem was
  visible with the following macro:
  {
     gStyle->SetOptFit(1111);
     h = new TH1F("h","h", 2,0.,1.);
     h->SetBinContent(1, 5E8);
     h->SetBinError(1, 4.9E8);
     h->Fit("pol0");
  }


git-svn-id: http://root.cern.ch/svn/root/trunk@27399 27541ba8-7e3a-0410-8455-c3a389f83636