message: Update bigquery_reader_ops.py
  Fix example code in comments by replacing tf.training.string_input_producer with tf.train.string_input_producer
diff: @@ -48,7 +48,7 @@ class BigQueryReader(io_ops.ReaderBase):
  features=features)
  # Populate a queue with the BigQuery Table partitions.
  - queue = tf.training.string_input_producer(reader.partitions())
  + queue = tf.train.string_input_producer(reader.partitions())
  # Read and parse examples.
  row_id, examples_serialized = reader.read(queue)
  