Turn off the error complaint when data reader is interrupted

[kuke]

If the data reader is interrupted by break in the for loop or ctrl+c from keyboard when loading batch data iteratively, there would output a lot of error complaints which look like

Process Process-9:
Process Process-10:
Traceback (most recent call last):
Process Process-5:
  File "/usr/lib/python2.7/multiprocessing/process.py", line 258, in _bootstrap
Traceback (most recent call last):
  File "/usr/lib/python2.7/multiprocessing/process.py", line 258, in _bootstrap
Traceback (most recent call last):
    self.run()
  File "/usr/lib/python2.7/multiprocessing/process.py", line 114, in run
  File "/usr/lib/python2.7/multiprocessing/process.py", line 258, in _bootstrap
    self._target(*self._args, **self._kwargs)
  File "/paddle_work/models/fluid/DeepASR/data_utils/data_reader.py", line 264, in ordered_processing_task
Exception in thread Thread-1:
Traceback (most recent call last):
  File "/usr/lib/python2.7/threading.py", line 801, in __bootstrap_inner
    self.run()
  File "/usr/lib/python2.7/threading.py", line 754, in run
    self.__target(*self.__args, **self.__kwargs)
  File "/paddle_work/models/fluid/DeepASR/data_utils/data_reader.py", line 317, in batch_assembling_task
    for sample in sample_generator():
  File "/paddle_work/models/fluid/DeepASR/data_utils/data_reader.py", line 291, in _sample_generator
    sample = sample_queue.get()
  File "<string>", line 2, in get
  File "/usr/lib/python2.7/multiprocessing/managers.py", line 759, in _callmethod
    kind, result = conn.recv()
IOError: [Errno 104] Connection reset by peer

    while order_id != out_order[0]:
  File "<string>", line 2, in __getitem__
  File "/usr/lib/python2.7/multiprocessing/managers.py", line 759, in _callmethod
    self.run()
    self.run()