Translations update from Weblate

Translations update from Weblate for AlekSIS/AlekSIS-App-Chronos.

Current translation status:

aleksis/apps/chronos/frontend/messages/de.json

 {
-  "chronos": {
-    "menu_title": "Stundenpläne"
-  }
-}
\ No newline at end of file
+    "chronos": {
+        "menu_title": "Stundenpläne",
+        "timetable": {
+            "menu_title_all": "Alle Stundenpläne",
+            "menu_title_my": "Mein Stundenplan"
+        },
+        "lessons": {
+            "menu_title_daily": "Tagesstunden"
+        },
+        "substitutions": {
+            "menu_title": "Vertretungen"
+        },
+        "supervisions": {
+            "menu_title_daily": "Tagesvertretungen"
+        }
+    }
+}