datenspuren mitschnitte: link to media.ccc.de for playback

xsl/datenspuren/xhtml5.xsl

@@ -269,6 +269,8 @@
     <xsl:for-each select="feed[1]">
       <xsl:for-each select="document(.)/rss/channel/item">
         <xsl:variable name="identifier" select="dc:identifier"/>
+        <xsl:variable name="slug"
+                      select="substring-before(substring-after(description, 'event on media: //media.ccc.de/'), '.html')"/>
         <xsl:variable name="title" select="substring-after(title, ': ')"/>
         <xsl:variable name="preview"
                       select="concat('https://static.media.ccc.de/media/events/datenspuren/2015/',
@@ -276,7 +278,11 @@
                               '-sd_preview.jpg')"/>
 
         <section class="resource">
-          <h4><xsl:value-of select="$title"/></h4>
+          <h4>
+            <a href="https://media.ccc.de/v/{$slug}">
+              <xsl:value-of select="$title"/>
+            </a>
+          </h4>
           <div class="preview">
             <img src="{$preview}" title="$title"/>
           </div>