Prepare payload and Fix middleware payload

Fix middleware call and exception (#53)

* fix Throwable handling

* fix bad array structure on middleware call

* Add tests

* fix array payload on middleware and listener call

* Cover payload if it is assoc

* improve payload check in publisher and dispatcher

* fix middleware test for array payload

* fix payload preparation in publisher

Co-authored-by: Eugene Kirdzei <e.ki@nuwber.com>