Cactus Code Thorn Outflow
Thorn Author(s)     : Roland Haas roland.haas@physics.gatech.edu
Thorn Maintainer(s) : Roland Haas roland.haas@physics.gatech.edu
                      Tanja Bode  tanja.bode@uni-tuebingen.de
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Purpose of the thorn:
Calculate the flux across a spherical surface.
