Rearrange home page, add link to blogs (#166)

* Make the news section most prominent by moving "about us" down
* Add a link to all blog posts (articles and events)
* Update group cards

Reviewed-on: #166
Reviewed-by: jtbx <jtbx@noreply.git.hamburg.ccc.de>

themes/ccchh/layouts/index.html

@@ -14,7 +14,7 @@
 
     {{ if or $upcoming $articleNew }}
     <div class="announcements">
-      <h2 id="neuigkeiten" class="on-hover-trg">Neuigkeiten <a href="#neuigkeiten" class="on-hover"><i class="fa-solid fa-link small"></i></a></h2>
+      <h2 id="aktuell" class="on-hover-trg">Aktuell <a href="#aktuell" class="on-hover"><i class="fa-solid fa-link small"></i></a></h2>
       {{- range $upcoming.ByDate }}
       <div class="announcement">
         {{- partial "blog-header.html" (dict "headingLink" true "level" 4 "reduced" true "page" . ) }}
@@ -44,6 +44,7 @@
         {{- end }}
       </div>
       {{- end }}
+      <p>Wir pflegen ein <a href="blog">Archiv aller Neuigkeiten</a>.</p>
     </div>
     {{- end }}