lang: correct language names

Low German/Saxon (NDS) is empty entirely, which caused discord lang
registration to error, so i've just filled in the name. Somebody
directly translated "English (US)" into italian instead of putting
Italian in italian, corrected that. Use some common sense!

discord.go

@@ -342,6 +342,7 @@ func (d *DiscordDaemon) registerCommands() {
 	commands[1].Options[0].Choices = make([]*dg.ApplicationCommandOptionChoice, len(d.app.storage.lang.Telegram))
 	i := 0
 	for code := range d.app.storage.lang.Telegram {
+		d.app.debug.Printf("Registering choice \"%s\":\"%s\"\n", d.app.storage.lang.Telegram[code].Meta.Name, code)
 		commands[1].Options[0].Choices[i] = &dg.ApplicationCommandOptionChoice{
 			Name:  d.app.storage.lang.Telegram[code].Meta.Name,
 			Value: code,

lang/common/it-it.json

@@ -1,6 +1,6 @@
 {
     "meta": {
-        "name": "Inglese (US)"
+        "name": "Italiano (IT)"
     },
     "strings": {
         "username": "Username",
@@ -28,4 +28,4 @@
     },
     "notifications": {},
     "quantityStrings": {}
-}
+}

lang/email/it-it.json

@@ -1,6 +1,6 @@
 {
     "meta": {
-        "name": "Inglese (US)"
+        "name": "Italiano (IT)"
     },
     "strings": {
         "ifItWasNotYou": "Se non sei stato tu, puoi ignorare questa email.",
@@ -49,4 +49,4 @@
         "clickBelow": "",
         "confirmEmail": ""
     }
-}
+}

lang/form/it-it.json

@@ -1,6 +1,6 @@
 {
     "meta": {
-        "name": "Inglese (US)"
+        "name": "Italiano (IT)"
     },
     "strings": {
         "pageTitle": "Crea Un Account Jellyfin",
@@ -48,4 +48,4 @@
             "plural": "Deve avere almeno {n} caratteri speciali"
         }
     }
-}
+}

lang/setup/nds.json

@@ -1,6 +1,6 @@
 {
     "meta": {
-        "name": ""
+        "name": "Nedderdütsch (NDS)"
     },
     "strings": {
         "pageTitle": "",

lang/telegram/it-it.json

@@ -1,6 +1,6 @@
 {
     "meta": {
-        "name": "Inglese (US)"
+        "name": "Italiano (IT)"
     },
     "strings": {
         "startMessage": "",
@@ -13,4 +13,4 @@
         "languageSet": "",
         "discordDMs": ""
     }
-}
+}

lang/telegram/nds.json

@@ -1,6 +1,6 @@
 {
     "meta": {
-        "name": ""
+        "name": "Nedderdütsch (NDS)"
     },
     "strings": {
         "startMessage": "",