Added hook for the Group navigation items

EVENTS.txt

@@ -191,6 +191,12 @@ StartPersonalGroupNav: beginning of personal group nav menu
 EndPersonalGroupNav: end of personal group nav menu (good place to add a menu item)
 - $action: action object being shown
 
+StartGroupGroupNav: Showing the group nav menu
+- $action: the current action
+
+EndGroupGroupNav: At the end of the group nav menu
+- $action: the current action
+
 StartEndHTML: just before the </html> tag
 - $action: action object being shown
 

lib/groupnav.php

@@ -79,6 +79,7 @@ class GroupNav extends Widget
         $nickname = $this->group->nickname;
 
         $this->out->elementStart('ul', array('class' => 'nav'));
+        if (Event::handle('StartGroupGroupNav', array($this))) {
             $this->out->menuItem(common_local_url('showgroup', array('nickname' =>
                                                                      $nickname)),
                                  _('Group'),
@@ -120,6 +121,8 @@ class GroupNav extends Widget
                                      $action_name == 'groupdesignsettings',
                                      'nav_group_design');
             }
+            Event::handle('EndGroupGroupNav', array($this));
+        }
         $this->out->elementEnd('ul');
     }
 }