Class FitConstants
==================
These data are the values needed to calculate the error matrices
to be used for the track fit. They also contain information about
the positions in z of the tracking layers and front face of the
first calorimeter downstream of the tracker.

The code for this class is in
 calice_reco/raw2calohit/include/TBTrackUtil/FitConstants.hh
 calice_reco/raw2calohit/src/TBTrackUtil/FitConstants.cc

The FitConstants are stored in the database in separate folders for
DESY, CERN and FNAL, namely

 DESY     /cd_calice_beam/TBTrack/FitConstants
 CERN /cd_calice_cernbeam/TBTrack/FitConstants
 FNAL /cd_calice_fnalbeam/TBTrack/FitConstants

The same values are used for data and simulation.