Added language and theme settings.

lang/nl-NL.json

@@ -28,6 +28,7 @@
   "label.enable-share-url": "Sta delen via openbare URL toe",
   "label.invalid": "Ongeldig",
   "label.invalid-domain": "Ongeldig domein",
+  "label.language": "Language",
   "label.last-days": "Laatste {x} dagen",
   "label.last-hours": "Laatste {x} uur",
   "label.logged-in-as": "Ingelogd als {username}",
@@ -50,6 +51,7 @@
   "label.settings": "Instellingen",
   "label.share-url": "URL delen",
   "label.single-day": "Enkele dag",
+  "label.theme": "Theme",
   "label.this-month": "Deze maand",
   "label.this-week": "Deze week",
   "label.this-year": "Dit jaar",