preparing release 2.5.7 updated and rebuilt the docs fixed the script

* NEWS configure.in: preparing release 2.5.7
* doc/*: updated and rebuilt the docs
* doc/apibuild.py: fixed the script
Daniel
diff --git a/doc/news.html b/doc/news.html
index deb2655..3d52637 100644
--- a/doc/news.html
+++ b/doc/news.html
@@ -105,6 +105,26 @@
   Schemas</a>
 </li>
 </ul>
+<h3>2.5.7: Apr 25 2003</h3>
+<ul>
+<li>Relax-NG: Compiling to regexp and streaming validation on top of the
+    xmlReader interface, added to xmllint --stream</li>
+  <li>xmlReader: Expand(), Next() and DOM access glue, bug fixes</li>
+  <li>Support for large files: RGN validated a 4.5GB instance</li>
+  <li>Thread support is now configured in by default</li>
+  <li>Fixes: update of the Trio code (Bjorn), WXS Date and Duration fixes
+    (Charles Bozeman), DTD and namespaces (Brent Hendricks), HTML push parser
+    and zero bytes handling, some missing Windows file path conversions,
+    behaviour of the parser and validator in the presence of &quot;out of memory&quot;
+    error conditions </li>
+  <li>extended the API to be able to plug a garbage collecting memory
+    allocator, added xmlMallocAtomic() and modified the allocations
+    accordingly.</li>
+  <li>Performances: removed excessive malloc() calls, speedup of the push and
+    xmlReader interfaces, removed excessive thread locking</li>
+  <li>Documentation: man page (John Fleck), xmlReader documentation</li>
+  <li>Python: adding binding for xmlCatalogAddLocal (Brent M Hendricks)</li>
+</ul>
 <h3>2.5.6: Apr 1 2003</h3>
 <ul>
 <li>Fixed W3C XML Schemas datatype, should be compliant now except for