This patch adds some security to the organize dialog.

1) If images are dragged from the content pane and dropped on a branch in the
   tree that the user only has view priviledges, then the drop is cancelled
   and the images are reverted.
2) The user cannot click on a branch, to which they only have view priviledges,
   the content pane does not change to the new album

modules/organize/controllers/organize.php

@@ -118,6 +118,7 @@ class Organize_Controller extends Controller {
     $v->album = $item;
     $keys = array_keys($parents);
     $v->selected = end($keys) == $item->id;
+    $v->can_edit= access::can("edit", $item);
     $v->children = array();
     $v->album_icon = "gBranchEmpty";