Add info on how to customize navigation (closes #104)

docs/customization.md

 # Customization
-SADE has been built to fit the needs of many projects creating digital editions.
-For a complete customization, an adaption of some XQuery modules may become
-necessary. But a few things are made to being set up by any user, as long as she is
-familiar with the basics of XML. When you want to start preparing your own
-instance, look at the file `config.xml` in the root collection of the application.
-There are many things you can set up.
 
-## Top Menu
-Edit the top menu (navbar) by entering your preferred structure in the file
-`navigation.xml`.
+SADE has been built to fit the needs of many projects creating digital editions. A few
+things can be set up by any user who is familiar with the basics of XML but for a deeper
+customization, an adaption of some XQuery modules may become necessary. If you want to
+start preparing your own instance, look at the `config.xml` file in the root collection
+of the application to set up the basics.
+
+## Top Menu / Navigation
+
+### General
+
+SADE provides an out-of-the-box mechanism to customize the website's top navigation. It
+is possible to add simple **buttons** or **dropdown menus**. All necessary adjustments
+can be made in the `/db/apps/sade/nagivation.xml` file.
+
+The configuration for the navigation shipped with SADE is this:
 
 ```xml
 <navigation>
-    <item label="Ein Text" link="view.html?id=text.md"/>
-    <submenu label="Links">
-        <item label="http://textgrid.de" link="http://textgrid.de"/>
+    <item label="Über SADE" label-en="About SADE" link="docs/about.md"/>
+    <submenu label="Dokumentation" label-en="Documentation">
+        <item label="Installation" label-en="Install" link="docs/install.md"/>
+        <item label="Features" label-en="Features" link="docs/features.md"/>
+        ...
+    </submenu>
+    <submenu label="Weiterführende Links" label-en="Further Links">
+        <item label="TextGrid Benutzerhandbuch" link="https://dev2.dariah.eu/wiki/display/TextGrid/User+Manual+2.0"/>
+        <item label="TextGrid Homepage" link="http://textgrid.de"/>
     </submenu>
 </navigation>
 ```
+
+In case you want to add a new top level link to the navigation, simply add a new `item`
+node as a child node of `navigation`, e.g.:
+
+```xml
+<item label="Metadata" link="view.html?id=metadata.md"/>
+```
+
+In the `label` attribute you can provide the link's text whereas the `link` attribute
+holds the path to the target resource.
+
+To create a label for a dropdown selection of links, add a `submenu` node as a child
+node of `navigation` with as many `item`s as you wish. Each `item` will be rendered as
+a link in the dropdown menu.
+
+```xml
+<submenu label="Features">
+    <item label="Feature 1" link="some/path/feature1.md"/>
+    <item label="Feature 2" link="some/path/feature2.md"/>
+    <item label="Feature 3" link="some/path/feature3.md"/>
+</submenu>
+```
+
+### Navigation labels and multilingual support
+
+Both the `item` and `subitem` nodes have a `label` attribute from which the text to be
+displayed is taken by default. In case you have [**multilanguage**](multilingual.md)
+support enabled, you can add more labels for other languages, e.g. `label-en` or
+`label-es`. Please note that these have to be listed in the multilanguage module
+configuration at `config.xml` as well; otherwise switiching languages might not work.

repo.xml

@@ -14,12 +14,13 @@
     <prepare>pre-install.xq</prepare>
     <finish>post-install.xq</finish>
     <changelog>
-      <change version="4.2.0">
+      <change version="5.0.0">
         <ul xmlns="http://www.w3.org/1999/xhtml">
           <li class="feat">Features
             <ul>
               <li>Add a documentation on release procedure</li>
-              <li>Add document how to use faceted search</li>
+              <li>Add documentation on how to use faceted search</li>
+              <li>Add documentation on how to customize the top navigation</li>
               <li>Pretty print test results on command line</li>
               <li>Server side pagination for search.html</li>
             </ul>