Make sasl2 conform to the DTD

inbox/sasl2.xml

@@ -4,7 +4,7 @@
 %ents;
 ]>
 <?xml-stylesheet type='text/xsl' href='xep.xsl'?>
-<xep xmlns="http://www.xmpp.org/extensions">
+<xep>
 <header>
   <title>Extensible SASL Profile</title>
   <abstract>This document describes a replacement for the SASL profile documented in RFC 6120 which allows for greater extensibility.</abstract>
@@ -16,7 +16,8 @@
   <dependencies>
     <spec>XMPP Core</spec>
   </dependencies>
-  <supersededby>None</supersededby>
+  <supersedes/>
+  <supersededby/>
   <shortname>sasl2</shortname>
   &dcridland;
   <revision>
@@ -205,7 +206,7 @@
 </section1>
 
 <section1 topic='XMPP Registrar Considerations' anchor='registrar'>
-	<p>None.</p>
+  <p>None.</p>
 </section1>
 
 <section1 topic='Acknowledgements' anchor='ack'>