Use xi:include in categories.xml

Author: tomschr

src/docbuild/config/xml/data/config.d/categories.xml

@@ -1,16 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <?xml-model href="file:../portal-config-schema.rnc" type="application/relax-ng-compact-syntax"?>
 <categories xmlns:xi="http://www.w3.org/2001/XInclude">
-  <category lang="en-us">
-    <item categoryid="about">
-      <title>Hello</title>
-    </item>
-  </category>
-  <category lang="de-de">
-    <item categoryid="about">
-      <title>Hallo</title>
-    </item>
-  </category>
-  <!--    <xi:include href="categories/en-us.xml" />-->
-    <!--<xi:include href="categories/de-de.xml" />-->
+    <xi:include href="categories/en-us.xml" />
+    <xi:include href="categories/de-de.xml" />
 </categories>