Add Creative Elements templates and update index files

- Introduced new templates for catalog, checkout, contact, and error pages.
- Implemented caching headers and redirection in index.php files across various directories.
- Enhanced product and layout templates for better integration with Creative Elements.
- Added backoffice header styles and scripts for improved UI/UX in the admin panel.

modules/creativeelements/views/templates/front/theme/_partials/footer.tpl

@@ -0,0 +1,14 @@
+{**
+ * Creative Elements - live Theme & Page Builder
+ *
+ * @author    WebshopWorks
+ * @copyright 2019-2022 WebshopWorks.com
+ * @license   One domain support license
+ *}
+{if isset($CE_FOOTER)}
+	{$CE_FOOTER|cefilter}
+{elseif file_exists("{$smarty.const._PS_THEME_DIR_}templates/_partials/footer.tpl")}
+	{include '[1]_partials/footer.tpl'}
+{elseif $smarty.const._PARENT_THEME_NAME_}
+	{include 'parent:_partials/footer.tpl'}
+{/if}