[DOCUMENTATION] English: add header tag

git-svn-id: http://framework.zend.com/svn/framework/standard/trunk@19887 44c647ce-9c0f-0410-b52a-842ac1e357ba

documentation/manual/en/ref/language-snippets.xml

@@ -1,4 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
+<!-- Reviewed: no -->
 
 <!-- links -->
 <!ENTITY lang                                   'en'>