Add host to config

src/server.cr

@@ -49,9 +49,7 @@ class Server
     {% if flag?(:release) %}
       Kemal.config.env = "production"
     {% end %}
-    unless Config.current.auth_proxy_header_name.empty?
-      Kemal.config.host_binding = "127.0.0.1"
-    end
+    Kemal.config.host_binding = Config.current.host
     Kemal.config.port = Config.current.port
     Kemal.run
   end