netty4.0.0.CR3升级到4.0.0.CR6

     因cr6与cr3 api变化比较多，所以改动类也较多.
netty4.0.0.CR3升级到4.0.0.CR6
Merge branch 'master' of gitlab.alibaba-inc.com:shijia.wxr/rocketmq
增加slaver地址
增加slaver地址
Merge branch 'master' of gitlab.alibaba-inc.com:shijia.wxr/rocketmq
#4 格式化代码
#92 优化Name Server
Merge https://github.com/alibaba/RocketMQ