Removed unnecessary SetDescription().

This manual copying of description is not needed after #282.

Author: psigen

src/prpy/base/robot.py

@@ -370,7 +370,6 @@ def PostProcessPath(self, path,
 
         # Copy the trajectory into the output environment.
         output_traj = CopyTrajectory(traj, env=self.GetEnv())
-        output_traj.SetDescription(path.GetDescription())
         return output_traj
 
     def ExecutePath(self, path, **kwargs):