pylint #83845 forward compatibility: pylint --help crashes [open]

when you run pylint --help in a directory where config with newer rules is present, pylint will crash with traceback. invalid config file should not affect --help rendering (for example, to give users a chance to lookup the correct option for the task):

$ pylint --version
Traceback (most recent call last):
  File "/usr/bin/pylint", line 4, in <module>
  File "/usr/lib/python2.7/site-packages/pylint/", line 833, in __init__
  File "/usr/lib/python2.7/site-packages/logilab/common/", line 649, in load_config_file
    provider.set_option(option, value, optdict=optdict)
  File "/usr/lib/python2.7/site-packages/pylint/", line 301, in set_option
  File "/usr/lib/python2.7/site-packages/pylint/", line 172, in disable
    msg = self.check_message_id(msgid)
  File "/usr/lib/python2.7/site-packages/pylint/", line 229, in check_message_id
    raise UnknownMessage('No such message id %s' % msgid)
pylint.utils.UnknownMessage: No such message id W1201
appeared in<not specified>
done in<not specified>
closed by<not specified>