updated docs

launch.py

@@ -877,7 +877,7 @@ if __name__ == '__main__':
     parser.add_argument('--crontab', action='store_true', dest='crontab',
                         default=False, help='Crontab mode. Implies --cache, '
                         'and not compatible with --node. When all jobs are '
-                        'done, crontab -r will remove all the user\' current '
+                        'done, crontab -r will remove all the user\'s current '
                         'crontab jobs. Default=False')
     parser.add_argument('--debug', action='store_true', dest='debug',
                         default=False, help='Debug print statements. Default=False')