Added language and theme settings.

lang/de-DE.json

@@ -28,6 +28,7 @@
   "label.enable-share-url": "Freigabe-URL aktivieren",
   "label.invalid": "Ungültig",
   "label.invalid-domain": "Ungültige Domain",
+  "label.language": "Language",
   "label.last-days": "Letzten {x} Tage",
   "label.last-hours": "Letzten {x} Stunden",
   "label.logged-in-as": "Angemeldet als {username}",
@@ -50,6 +51,7 @@
   "label.settings": "Einstellungen",
   "label.share-url": "Freigabe-URL",
   "label.single-day": "Ein Tag",
+  "label.theme": "Theme",
   "label.this-month": "Diesen Monat",
   "label.this-week": "Diese Woche",
   "label.this-year": "Dieses Jahr",