Added some docs to CI core files
diff --git a/system/core/Input.php b/system/core/Input.php
index 64d6c36..bc202b3 100755
--- a/system/core/Input.php
+++ b/system/core/Input.php
@@ -618,6 +618,8 @@
 	 * In Apache, you can simply call apache_request_headers(), however for
 	 * people running other webservers the function is undefined.
 	 *
+	 * @param	bool XSS cleaning
+	 *
 	 * @return array
 	 */
 	public function request_headers($xss_clean = FALSE)