* Add apdex function to OAL

* Add empty line

* Setup config watcher

* Add identifier type to function parameter

* Add config test

* Update score algorithm

* Replace responseCode with status

* Add comments about apdex score algorithm

* Add docs

* Add e2e test case

* Update test case

* Fix disptch class generating error

* Update value name of apdex metric

* Tuning threshold

* Fix single tolerated point bug