message: code review: rool back compilation error as cgal will make it fail
diff: # include <boost/iterator/function_output_iterator.hpp>
  #include <gudhi/Kd_tree_search.h>
  -#include <CGAL/version.h> // for CGAL_VERSION_NR
  #ifdef GUDHI_SUBSAMPLING_PROFILING
  #include <gudhi/Clock.h>
  #endif
  #include <cstddef>
  #include <vector>
  -// Make compilation fail - required for external projects
  -#if CGAL_VERSION_NR < 1041101000
  -# error subsampling::sparsify_point_set is only available with CGAL >= 4.11
  -#endif
  -
  namespace Gudhi {
  namespace subsampling {
  