[Numerics] add constant for GFC3D solver
[Numerics] add constant for GFC3D solver

bremond/siconos,radarsat1/siconos,siconos/siconos,siconos/siconos,radarsat1/siconos,bremond/siconos,bremond/siconos,fperignon/siconos,radarsat1/siconos,siconos/siconos,bremond/siconos,fperignon/siconos,fperignon/siconos,radarsat1/siconos,bremond/siconos,radarsat1/siconos,siconos/siconos,fperignon/siconos,fperignon/siconos