Datadog unix socket support

[benwilson512]

Hey folks!

Does this project support using unix sockets for data dog? I've got a PR into statix lexmag/statix#35 to enable this, and I'd be happy to recreate that here.

[zachdaniel]

We don't support it, but if you'd like to add it that would be great :)

[GregMefford]

Yeah that looks neat! 👍 It's pretty common (I think) for folks to run the DD Agent on the same host as their Elixir app and point the traces at localhost, so a Unix socket might be better for that use-case.