Improve maint page and enable redirect checks (safing#240)

Author: dhaavi

_includes/head.html

@@ -34,3 +34,7 @@
 <link rel="stylesheet" href="{{ site.assets_url }}css/main.css" type="text/css">
 
 {% include plausible.html %}
+
+{%- if page.redirect -%}  
+<meta http-equiv="refresh" content="{{ page.redirect_after | default: 0 }};url={{ page.redirect }}" />
+{%- endif %}

support/maintenance.html

@@ -1,18 +1,22 @@
 ---
 layout: page
 title: Maintenance
+redirect: /support/maintenance
+redirect_after: 60
 ---
 
 <section class="publication-layout">
   <div class="markdown-container max-w-5xl">
     <h1 class="font-extrabold">
-      Maintenance In Progress
+      Account Server is in Maintenance
     </h1>
     <p style="margin-top: 50px;">
-      You have been redirected to here because the service you are trying to access is currently under maintenance.
+      You have been redirected here because the Account Server is currently under maintenance.<br>
+      It will be available again by 10. January 16:00 UTC.
     </p>
     <p>
-      It will be available again shortly.
+      This page will automatically check the status and redirect you once maintenance has ended.<br>
+      You may also refresh this page to check.
     </p>
   </div>
 </section>