erp5_free_subscription: Update Base_unsusbscribe to work for none anonymous and redirect

bt5/erp5_free_subscription/SkinTemplateItem/portal_skins/erp5_free_subscription/Base_unsubscribeFromEvent.xml

@@ -57,13 +57,10 @@ portal = context.getPortalObject()\n
 request = context.REQUEST\n
 event_id = request[\'id\']\n
 \n
-user = portal.ERP5Site_getAuthenticatedMemberPersonValue()\n
-# If we have a logged in user it\'s probably a backoffice agent.\n
-if user is None:\n
-  # If the referer contains the url of the event we are probably viewing the event\n
-  # from ERP5 interface. We do not want to mark the event as delivered in that case\n
-  # It can also be from fckeditor, in this case we don\'t have the event url in REFERER.\n
-  if not ( (\'/event_module/%s\' % event_id) in request.HTTP_REFERER or \'fckeditor\' in request.HTTP_REFERER):\n
+# If the referer contains the url of the event we are probably viewing the event\n
+# from ERP5 interface. We do not want to mark the event as delivered in that case\n
+# It can also be from fckeditor, in this case we don\'t have the event url in REFERER.\n
+if not ( (\'/event_module/%s\' % event_id) in request.HTTP_REFERER or \'fckeditor\' in request.HTTP_REFERER):\n
   if portal.Base_getHMACHexdigest(portal.Base_getEventHMACKey(), event_id) != request["hash"]:\n
     from zExceptions import Unauthorized\n
     raise Unauthorized()\n
@@ -73,8 +70,8 @@ if user is None:\n
         event_id=request[\'id\'], \n
         hmac=request["hash"])\n
 \n
-# serve the web-page that will display a "Sucessfully unsubscribe" message\n
-return context.index_html(request, request.RESPONSE, format=None)\n
+# serve the image\n
+return context.Base_redirect(\'\')\n
 </string> </value>
         </item>
         <item>