keep DIR_SEP for 3rd party compatability

NEWS

@@ -1,4 +1,4 @@
-  - remove DIR_SEP, use DIRECTORY_SEPARATOR exclusively (Monte)
+  - use DIRECTORY_SEPARATOR exclusively, keep DIR_SEP for BC (Monte)
   - changed "link" to "href" in html_image. "link" is still working
     but deprecated (messju)
   - html_image always renders an alt-tag now (default alt="") (messju)

libs/Smarty.class.php

@@ -50,6 +50,10 @@
  * application has not already defined it.
  */
 
+if(!defined('DIR_SEP')) {
+	define('DIR_SEP', DIRECTORY_SEPARATOR);
+}
+
 /**
  * Sets SMARTY_DIR only if user application has not already defined it
  */