New status_header code, and WP-DB bail() errors send a 503 Service Unavailable. see #2409

Also, the new header code to text array has 302 as Found. fixes #4183


git-svn-id: https://develop.svn.wordpress.org/trunk@5446 602fd350-edb4-49c9-b593-d223f7449a82

wp-includes/wp-db.php

@@ -369,7 +369,8 @@ class wpdb {
 	function bail($message) { // Just wraps errors in a nice header and footer
 		if ( !$this->show_errors )
 			return false;
-
+		
+		status_header( 503 );
 		header('Content-Type: text/html; charset=utf-8');
 
 		if (strpos($_SERVER['PHP_SELF'], 'wp-admin') !== false)