關閉jieba結巴分詞日志輸出

使用結巴分詞，會輸出如下日志：

Building prefix dict from /usr/lib/python2.7/site-packages/jieba/dict.txt ...
Loading model from cache /tmp/jieba.cache
Loading model cost 0.182227134705 seconds.
Prefix dict has been built succesfully.      

logging日志級别（5個等級），從低到高分别是：

DEBUG
INFO
WARNING
ERROR
CRITICAL      

不顯示debug資訊，隻要大于 logging.DEBUG 級别即可，比如：

import logging

jieba.setLogLevel(logging.INFO)      

參考：

jieba如何關閉stderr的日志 #255