message: make th same example as in C++
diff: #!/usr/bin/env python
  -from gudhi import WitnessComplex, SimplexTree
  +from gudhi import StrongWitnessComplex, SimplexTree
  """This file is part of the Gudhi Library. The Gudhi library
  (Geometric Understanding in Higher Dimensions) is a generic C++
  @@ -36,7 +36,7 @@ nearest_landmark_table = [[[0, 0], [1, 1], [2, 2], [3, 3], [4, 4]],
  [[3, 0], [4, 1], [0, 2], [1, 3], [2, 4]],
  [[4, 0], [0, 1], [1, 2], [2, 3], [3, 4]]]
  -witness_complex = WitnessComplex(nearest_landmark_table=nearest_landmark_table)
  +witness_complex = StrongWitnessComplex(nearest_landmark_table=nearest_landmark_table)
  simplex_tree = witness_complex.create_simplex_tree(max_alpha_square=4.1)
  message = "Number of simplices: " + repr(simplex_tree.num_simplices())
  