Add port to url helper calls.

Use config.fqdn instead of Settings.hostname If `Settings.hostname` is defined, it is the same as `config.fqdn`, so this is only really a change if `Settings.hostname` is `nil`. This doesn't change the deployment config. There we explicitly use `Settings.hostname` because we don't want to read the hostname from our development machines when deploying.

add serializers for formality_level and license.