spec/Overview.html 1.1237 2058 Make it clear that xml:lang is namespace

Make it clear that xml:lang is namespaced. (whatwg r2058)

language
http://people.w3.org/mike/diffs/html5/spec/Overview.1.1237.html#language

http://people.w3.org/mike/diffs/html5/spec/Overview.diff.html
http://dev.w3.org/cvsweb/html5/spec/Overview.html?r1=1.1236&r2=1.1237&f=h
http://html5.org/tools/web-apps-tracker?from=2057&to=2058

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RCS file: /sources/public/html5/spec/Overview.html,v
retrieving revision 1.1236
retrieving revision 1.1237
diff -u -d -r1.1236 -r1.1237
--- Overview.html	12 Aug 2008 10:02:08 -0000	1.1236
+++ Overview.html	12 Aug 2008 10:19:09 -0000	1.1237
@@ -7954,7 +7954,10 @@
    href="#references">[RFC3066]</a>
 
   <p>The <code title=attr-xml-lang><a href="#xmllang">xml:lang</a></code>
-   attribute is defined in XML. <a href="#references">[XML]</a>
+   attribute (that is, the <code title="">lang</code> attribute with the
+   <code title="">xml</code> prefix in the <code
+   title="">http://www.w3.org/XML/1998/namespace</code> namespace) is defined
+   in XML. <a href="#references">[XML]</a>
 
   <p>If these attributes are omitted from an element, then it implies that
    the language of this element is the same as the language of the parent