message: csv file and not OFF
diff: #include <gudhi/Rips_complex.h>
  -// to construct Rips_complex from a OFF file of points
  +// to construct Rips_complex from a csv file representing a distance matrix
  #include <gudhi/reader_utils.h>
  #include <gudhi/Simplex_tree.h>
  #include <gudhi/distance_functions.h>
  