gemspec on all logstash plugins points "homepage" to Logstash Documentation

When going to the webpage of a plugin on rubygems like [output kafka](https://rubygems.org/gems/logstash-output-kafka), the "Homepage" link will always go to http://www.elastic.co/guide/en/logstash/current/index.html.

Can we do better? Maybe point it to [its individual documentation page](https://www.elastic.co/guide/en/logstash/current/plugins-outputs-kafka.html)?
I know we don't publish this url for all plugins but having a bad default because of a corner case doesn't seem right. An alternative is the github repository.