Add maintenance page using custom error code

package.json

@@ -1,6 +1,6 @@
 {
     "name": "error-pages",
-    "version": "1.3.1",
+    "version": "1.3.2",
     "description": "Error pages for my website.",
     "author": "Felix W. Dekker",
     "browser": "dist/bundle.js",

src/main/_data/error-pages.json

@@ -98,5 +98,10 @@
     {
         "name": "HTTP version not supported",
         "code": "505"
+    },
+    {
+        "name": "Maintenance",
+        "code": "590",
+        "maintenance": "true"
     }
 ]

src/main/template.njk

@@ -37,9 +37,13 @@ permalink: "{{ errorPage.code | slug }}.html"
     <div id="nav"></div>
     <div id="contents">
         <section class="container">
-            <h3>{{ errorPage.name }} <small>({{ errorPage.code }})</small></h3>
+            <h3>{{ errorPage.name }}{% if not errorPage.maintenance %} <small>({{ errorPage.code }})</small>{% endif %}</h3>
             Sorry for the inconvenience.
-            You may want to try going to <a href="https://fwdekker.com/">this website's homepage</a>.
+            {% if errorPage.maintenance %}
+                Please try again in a minute or so.
+            {% else %}
+                You may want to try going to <a href="https://fwdekker.com/">this website's homepage</a>.
+            {% endif %}
         </section>
     </div>
     <div id="footer"></div>