Running in prod

So, I deployed beacon and live admin following the guides. Everything works ok.
But when I do a `MIX_ENV=prod mix phx.server' everything is messed up.
I understand (vaguely) why you needed to add the two new endpoints (proxy and blog), but it would be extremely helpful to have a small doc explaining how to run it in prod. Because it completely modified my existing configuration for the prod environment, adding a mix of `http` and `https`, adding some random ports, binding to all the interfaces while my initial config was 127.0.0.1 and so on and so fort.

Thanks!