preparing 2.4.7 switched to the latest xmllint manual page from John

* configure.in: preparing 2.4.7
* Makefile.am doc/Makefile.am: switched to the latest xmllint
  manual page from John
* doc/*: updated the doc and rebuilt the generated pages
Daniel
diff --git a/doc/site.xsl b/doc/site.xsl
index aa58934..b126472 100644
--- a/doc/site.xsl
+++ b/doc/site.xsl
@@ -85,6 +85,9 @@
       <xsl:when test="$name = '#Memory'">
         <xsl:text>xmlmem.html</xsl:text>
       </xsl:when>
+      <xsl:when test="$name = '#Thread'">
+        <xsl:text>threads.html</xsl:text>
+      </xsl:when>
       <xsl:when test="$name = '#FAQ'">
         <xsl:text>FAQ.html</xsl:text>
       </xsl:when>