Warn about old version of nodejs

Author: Dave Conway-Jones

dist/dashboard.appcache

@@ -1,5 +1,5 @@
 CACHE MANIFEST
-# Time: Thu Dec 16 2021 16:29:45 GMT+0000 (Greenwich Mean Time)
+# Time: Fri Dec 17 2021 17:22:23 GMT+0000 (Greenwich Mean Time)
 
 CACHE:
 i18n.js
@@ -26,4 +26,4 @@ loading.html
 NETWORK:
 *
 
-# hash: 676bcd674984ff87257ddbf21d07bf983416c7943e422cc1b664ca7010bde83a
+# hash: 9eb1e7b63970218616a9f3deb95704fa38859984a0cc5dbd91f0ef036dfd4942