Add basic page layout demo

index.html

@@ -62,6 +62,7 @@
       <h3 class="sg-sub-heading sg-section-h3">Generische Layouts</h3>
       <ul class="sg-index-list">
         <li><a href="./patterns/card-listen-seite.html">Card Listen Seite</a></li>
+        <li><a href="./patterns/page-layout-basic.html">Page Layout Basic</a></li>
         <li><a href="./patterns/card-listen-fundamentalanalyse-mobile.html">Card Listen Fundamentalanalyse Mobile</a></li>
       </ul>