Add windows filename rule as an option for upload files
diff --git a/system/libraries/Upload.php b/system/libraries/Upload.php
index 8542804..62eca6f 100644
--- a/system/libraries/Upload.php
+++ b/system/libraries/Upload.php
@@ -143,6 +143,13 @@
 	public $file_ext_tolower		= FALSE;
 
 	/**
+	 * Filename Rule
+	 *
+	 * @var	string
+	 */
+	public $filename_rule		= 'default';
+
+	/**
 	 * Upload path
 	 *
 	 * @var	string
@@ -315,7 +322,8 @@
 					'detect_mime'			=> TRUE,
 					'xss_clean'			=> FALSE,
 					'temp_prefix'			=> 'temp_file_',
-					'client_name'			=> ''
+					'client_name'			=> '',
+					'filename_rule'			=> 'default',
 				);
 
 		foreach ($defaults as $key => $val)
@@ -472,7 +480,7 @@
 
 		// Sanitize the file name for security
 		$CI =& get_instance();
-		$this->file_name = $CI->security->sanitize_filename($this->file_name);
+		$this->file_name = $CI->security->sanitize_filename($this->file_name, FALSE, $this->filename_rule);
 
 		// Truncate the file name if it's too long
 		if ($this->max_filename > 0)