Multiplayer improvements and reupload score on error

- In multiplayer you will play at the bottom if you joined second
- Add a dialog to song select that score has not been saved
- Uploads the score when logged in again
- Translate error messages from the server

config.example.json

@@ -2,5 +2,5 @@
     "songs_baseurl": "",
     "assets_baseurl": "",
     "email": "",
-    "_accounts": true
+    "accounts": true
 }