VisualizeSailAttitude:

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   Visualize the attitude of a sail in 3D using a patch and sun vector.
   The sail is assumed to have a body frame with a +X front normal and the
   sail membrane in the Y/Z plane.
   If a second quaternion is entered clock angle is computed from the reference 
   y axis to the sail back normal (nominal force direction).

   Since version 7.
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   Form:
   [cone, clock] = VisualizeSailAttitude( q, uSun, q2, c )
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   Inputs
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   q                 (4,1)  Sail attitude quaternion (inertial to body)
   uSun              (3,1)  Vector to sun  (inertial)
   q2                (4,1)  Second set of reference axes (inertial to ref)
   c                 (1,1)  Sign convention for clock angle, measured
                            about direction TO the sun (+1) or AWAY from
                            the sun (-1). Default is +1.

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   Outputs
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   cone              (1,1)  Cone angle
   clock             (1,1)  Clock angle

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