Error handler - Counter and option to log when a retry became success

Asked on twitter
https://twitter.com/luistrigueiros/status/1053039644093366272

It may be good to have a way to know if a message that has first failed and then with retries from the error handler then became succesful. We should be able to see this with

• counter in the mbean
• log message in the logs, option to configure the logging level.