Add translations for statement-based searches in main frontend

frontend/en/navigation.json

@@ -17,6 +17,7 @@
         "articles": "Articles",
         "events": "Events",
         "select_language": "Select language",
-        "join_us": "Join us"
+        "join_us": "Join us",
+        "browse_backgrounds": "Browse \"background information\""
     }
 }