[vtkusers] VTK Wiki, VTK/Examples/ContoursToSurface fixed

[Dean Inglis]

I spent some time revising VTK/Examples/ContoursToSurface.cxx
in the broken examples section of the wiki.  The example primarily
illustrates use of vtkVoxelContoursToSurfaceFilter.  The two major
revisions to getting it to work were to:
1) not use lines as contours, but as closed polygons instead:
  vtkCutter was being used to cut a vtkSphereSource with an implicit
  vtkPlane which led to a series of disconnected (unclosed) straight line 
segments,
  each segment being comprised of just two points.  I changed this to 
explicitly
  generate a series of discs from x-y planes slicing a unit sphere
2) the coordinates of the points have to be converted into integer (ijk)
    representation, and so, one has to figure out a "nice" sampling rate and 
scale
   accordingly

Im not sure where the wiki page for this should go, so would someone take
a look and redirect accordingly?

Dean