Replacing GenEvent with Registry

[tchoutri]

Hi! GenEvent is a deprecated module of Elixir's standard library, and as I can see from events.ex, it could very well be replaced by Elixir's new Registry application.

I'd love to provide a Pull Request for such a change, ExDNS is a very interesting project, and I would like to contribute to your efforts.

[aeden]

By all means, feel free. I started something here: #5

If you want you can throw that away and start fresh.

[tchoutri]

Thank you very much for the indications :)

[tchoutri]

@aeden I see that the elixir version is ~> 1.2. Is that alright to raise the bar so we can use all the nice things Elixir 1.6 provides?
I'd be more than willing to even write a contributor's guide to help people set an environment up if their package manager doesn't provide Elixir 1.6 and Erlang 20.2.

[aeden]

Go for it.

[tchoutri]

Thanks :)