Clear some spaces and fix some inconsistencies in application/ php files
diff --git a/application/errors/error_404.php b/application/errors/error_404.php
index 9af9e39..7460329 100644
--- a/application/errors/error_404.php
+++ b/application/errors/error_404.php
@@ -1,13 +1,13 @@
-<?php
+<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
 /**
  * CodeIgniter
  *
  * An open source application development framework for PHP 5.2.4 or newer
  *
  * NOTICE OF LICENSE
- * 
+ *
  * Licensed under the Academic Free License version 3.0
- * 
+ *
  * This source file is subject to the Academic Free License (AFL 3.0) that is
  * bundled with this package in the files license_afl.txt / license_afl.rst.
  * It is also available through the world wide web at this URL:
@@ -24,9 +24,7 @@
  * @since		Version 1.0
  * @filesource
  */
-?>
-
-<!DOCTYPE html>
+?><!DOCTYPE html>
 <html lang="en">
 <head>
 <meta charset="utf-8">