[Feature Request] Add gitea support and v6 version

Hello @deankarn I'm interested in use this wonderful lib to some of our projects. But we are currently using gitea and I would like to see merged this  PR https://github.com/go-playground/webhooks/pull/81  Any plans to merge? 
About version , I've seen latest v6.0.0-beta.2 from january. Any plans to release v6.0.0-final version ?