Partially revert PR #2190

The core shouldn't depend on constants that are not defined by itself
diff --git a/system/libraries/Zip.php b/system/libraries/Zip.php
index 43abfba..c634b11 100644
--- a/system/libraries/Zip.php
+++ b/system/libraries/Zip.php
@@ -398,7 +398,7 @@
 	 */
 	public function archive($filepath)
 	{
-		if ( ! ($fp = @fopen($filepath, FOPEN_WRITE_CREATE_DESTRUCTIVE)))
+		if ( ! ($fp = @fopen($filepath, 'w+b')))
 		{
 			return FALSE;
 		}