Higher verbosity when parsing Hadoop conf files

[simleo]

hadoop_utils.PathFinder.hadoop_params could be a bit more verbose about failed parsing attempts (which file could not be parsed and why). Something like:

                 try:
                     params.update(parse_hadoop_conf_file(fn))
-                except (IOError, HadoopXMLError):
+                except (IOError, HadoopXMLError) as e:
+                    print("could not parse %s: %r" % (fn, e))
                     pass  # silently ignore, as in Hadoop

But done properly, i.e., via a warning or log message.