Make user manual in an index.html

This is in preparation to make it the root of gh-pages. A link is added
to the reference manual.

Author: bmerry

doc/clogs-user.xml

@@ -482,6 +482,14 @@ problem.setTunePolicy(policy);
         </section>
     </chapter>
 
+    <chapter id="reference">
+        <title>Reference manual</title>
+        <para>
+            The reference manual is in a <ulink
+                url="html/index.html">separate document</ulink>.
+        </para>
+    </chapter>
+
     <chapter id="performance">
         <title>Performance</title>
         <para>

wscript

@@ -272,7 +272,7 @@ def build(bld):
     if bld.env['XSLTPROC']:
         bld(rule='${XSLTPROC} --xinclude --stringparam clogs.version ' + VERSION + ' -o ${TGT} ${SRC}',
             source=['doc/clogs-user-xml.xsl', 'doc/clogs-user.xml'],
-            target='doc/clogs-user.html')
+            target='doc/index.html')
         bld(rule=simple_copy,
             source='doc/clogs-user.in.css',
             target='doc/clogs-user.css')