remove halo nodes for the turbovertex 2D and add comments
remove halo nodes for the turbovertex 2D and add comments

drewkett/SU2,hlkline/SU2,srange/SU2,drewkett/SU2,srange/SU2,hlkline/SU2,drewkett/SU2,drewkett/SU2,drewkett/SU2,hlkline/SU2,hlkline/SU2,hlkline/SU2,srange/SU2,srange/SU2