Add GenericObject plugin files and assets

- Introduced default icon images in PNG and SVG formats.
- Added example icons for car and cube in SVG format.
- Created setup file for the GenericObject plugin with versioning and directory definitions.
- Included a header file with licensing information for the plugin.
- Added a remove.txt file with instructions for safe deletion.

plugins/genericobject/front/commontreedropdown.php

@@ -0,0 +1,32 @@
+<?php
+
+/**
+ * -------------------------------------------------------------------------
+ * GenericObject plugin for GLPI
+ * -------------------------------------------------------------------------
+ *
+ * LICENSE
+ *
+ * This file is part of GenericObject.
+ *
+ * GenericObject is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * GenericObject is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with GenericObject. If not, see <http://www.gnu.org/licenses/>.
+ * -------------------------------------------------------------------------
+ * @copyright Copyright (C) 2009-2022 by GenericObject plugin team.
+ * @license   GPLv3 https://www.gnu.org/licenses/gpl-3.0.html
+ * @link      https://github.com/pluginsGLPI/genericobject
+ * -------------------------------------------------------------------------
+ */
+
+include ("../../../inc/includes.php");
+include ("./commondropdown.php");