update .gitattributes to treat new cpp file as binary
update .gitattributes to treat new cpp file as binary

scikit-hep/root_numpy,scikit-hep/root_numpy,rootpy/root_numpy,ndawe/root_numpy,ndawe/root_numpy,ibab/root_numpy,rootpy/root_numpy,scikit-hep/root_numpy,rootpy/root_numpy,ibab/root_numpy,ibab/root_numpy,rootpy/root_numpy,scikit-hep/root_numpy,ndawe/root_numpy,ndawe/root_numpy,ibab/root_numpy