message: Update comment for GUDHI_PYTHON_MODULES_EXTRA
diff: @@ -26,7 +26,10 @@ __all__ = [@GUDHI_PYTHON_MODULES@ @GUDHI_PYTHON_MODULES_EXTRA@]
  __available_modules = ''
  __missing_modules = ''
  -# try to import * from gudhi.__module_name
  +# Try to import * from gudhi.__module_name for default modules.
  +# Extra modules require an explicit import by the user (mostly because of
  +# unusual dependencies, but also to avoid cluttering namespace gudhi and
  +# speed up the basic import)
  for __module_name in [@GUDHI_PYTHON_MODULES@]:
  try:
  __module = import_module('gudhi.' + __module_name)
  