Added event handlers to logout action

EVENTS.txt

@@ -103,3 +103,9 @@ EndPublicGroupNav: At the end of the public group nav menu
 RouterInitialized: After the router instance has been initialized
 - $m: the Net_URL_Mapper that has just been set up
 
+StartLogout: Before logging out
+- $action: the logout action
+
+EndLogout: After logging out
+- $action: the logout action
+

actions/logout.php

@@ -70,10 +70,20 @@ class LogoutAction extends Action
         if (!common_logged_in()) {
             $this->clientError(_('Not logged in.'));
         } else {
-            common_set_user(null);
-            common_real_login(false); // not logged in
-            common_forgetme(); // don't log back in!
+            if (Event::handle('StartLogout', array($this))) {
+                $this->logout();
+            }
+            Event::handle('EndLogout', array($this));
+
             common_redirect(common_local_url('public'), 303);
         }
     }
+
+    function logout()
+    {
+        common_set_user(null);
+        common_real_login(false); // not logged in
+        common_forgetme(); // don't log back in!
+    }
+
 }