kafka-python 停止消费

使用kafka-python时，不消费数据，也没有异常

换为pykafka库后解决

使用例子

from pykafka import KafkaClient

client = KafkaClient(hosts='127.0.0.1:9092')
topic = client.topics['logsget']

consumer = topic.get_simple_consumer()
for msg in consumer:
    if msg is not None:
        print msg.value