* add plugin netty-socketio https://github.com/mrniko/netty-socketio

* delete create exit span interceptor.

* delete create exit span interceptor testcase.

* delete create exit span interceptor testcase.

* add constructor test unit

* change bind on random port in test case

* reverse upstream master whitespace

* resolve build_id param

* delete health check segment test case

* add ContextManager.isActive check before use activeSpan invoke

* remove unnecessary code and blank line