Resolve "Data management for the Models `Room` and `SchoolTerm`"

Closes #831 (closed), #715 (closed)

This MR introduces generic components for crud data handling.

aleksis/core/frontend/app/dateTimeFormats.js

@@ -26,6 +26,10 @@ const dateTimeFormats = {
       hour: "numeric",
       minute: "numeric",
     },
+    shortTime: {
+      hour: "numeric",
+      minute: "numeric",
+    },
   },
   de: {
     short: {
@@ -53,6 +57,10 @@ const dateTimeFormats = {
       hour: "numeric",
       minute: "numeric",
     },
+    shortTime: {
+      hour: "numeric",
+      minute: "numeric",
+    },
   },
 };