* [Improvement][remote] improvement netty eventLoopGroup
If you are running on linux you can use EpollEventLoopGroup and so get better performance, less GC and have more advanced features that are only available on linux.

* reformat code

* utility classes should not have public constructors

* reformat code

* reformat code

* reformat code

* add test

* code style

* add test

* add test

* fix test error

* add test

* test

* test

* add test config

* add test config