(fix) read me

Author: ylgrgyq

README.md

@@ -1,7 +1,9 @@
 # Kafka Java Consumer
 
 [![Build Status](https://api.travis-ci.org/leancloud/kafka-java-consumer.svg?branch=master)](https://travis-ci.org/leancloud/kafka-java-consumer)
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 Kafka is a greate lib which is very versatile and flexible, but many things may go wrong if you use it without great care and a good understanding about Kafka internals.  Next we will talk about some pitfalls on the consumer side which are easy to encounter with.