HandlerFeedGenerator: Improvements to make feed vlaid

template/quitesimple/feeds/atomentry

@@ -3,5 +3,6 @@
     <link href="{qswiki:var:entryurl}"/>
     <id>{qswiki:var:entryid}</id>
     <published>{qswiki:var:entrypublished}</published>
+    <updated>{qswiki:var:entryupdated}</updated>
     <content type="html">{qswiki:var:entrycontent}</content>
 </entry>

template/quitesimple/feeds/atomheader

@@ -5,4 +5,5 @@
   </author>
   <title>{qswiki:config:wikiname} - {qswiki:var:subtitle}</title>
   <id>{qswiki:var:atomfeeduniqueid}</id>
+  <link rel="self" href="{qswiki:var:atomselflink}"/>
   <updated>{qswiki:var:atomfeedupdate}</updated>