[Bugfix] Expose port in Dockerfile and force IPv4 (#129)

* Exposes port on built image

* Forced IPv4

* Added current version to sidebar

config/runtime.exs

@@ -102,7 +102,7 @@ if config_env() == :prod do
       # Set it to  {0, 0, 0, 0, 0, 0, 0, 1} for local network only access.
       # See the documentation on https://hexdocs.pm/plug_cowboy/Plug.Cowboy.html
       # for details about using IPv6 vs IPv4 and loopback vs public addresses.
-      ip: {0, 0, 0, 0, 0, 0, 0, 0},
+      ip: {0, 0, 0, 0},
       port: String.to_integer(System.get_env("PORT") || "4000")
     ],
     secret_key_base: secret_key_base