Fix problem with <category>

Now the category works as expected

Author: tomschr

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

@@ -1,6 +1,16 @@
 <?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">
-    <xi:include href="categories/en-us.xml" />
+  <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" />-->
 </categories>

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

@@ -1,4 +1,6 @@
-<category lang="de-de" default="false">
+<?xml-model href="file:../../portal-config-schema.rnc" type="application/relax-ng-compact-syntax"?>
+
+<category lang="de-de">
   <language categoryid="about" title="Über" />
   <language categoryid="deployment" title="Deployment" />
   <language categoryid="inital-config" title="Initiale Konfiguration" />

src/docbuild/config/xml/data/config.d/categories/en-us.xml

@@ -5,4 +5,4 @@
   <language categoryid="deployment" title="Deployment" />
   <language categoryid="inital-config" title="Initial configuration" />
   <!-- ... more entries ... -->
-</category>
+</category>

src/docbuild/config/xml/data/portal-config-schema.rnc

@@ -670,10 +670,10 @@ div {
     ## Wrapper for all category elements
     element categories {
       ds.xmlbase.attr?,
-      ds.category.default,
-      ds.category.translation*
-      # (ds.category.translation & xi.include)*
-      # (ds._category & xi.include*)+
+      (
+        (ds.category.default, ds.category.translation*)
+        | xi.include+
+      )
     }
 }
 
@@ -711,40 +711,26 @@ div {
     element category {
       ds.xmlbase.attr?,
       ds.lang.attr,
-      ds.category_language
+      ds.category_language+
     }
 }
 
 
 [
-  db:refname [ "language (variant 1)" ]
+  db:refname [ "language" ]
   db:refpurpose [ "Metadata for category displayed on product detail navigational page" ]
 ]
 div {
 ds.category_language =
   ## Metadata for category displayed on product detail navigational page
-  element language {
+  element language {  # TODO: language
     ds.categoryid.attr,
     ds.title.attr,
     ds.htmlblock*
   }
 }
 
 
-[
-  db:refname [ "language (variant 2)" ]
-  db:refpurpose [ "Metadata for category displayed on product detail navigational page (dependent languages)" ]
-]
-div {
-ds.categorylanguage_translation =
-  ## Metadata for category displayed on product detail navigational page (dependent languages, third-level category)
-  element language {
-    #ds.lang.attr,
-    ds.title.attr,
-    ds.htmlblock*
-  }
-}
-
 
 # DOCSETS
 [