Log Message:
Update to 2.5.4.
* Conformance testing and lot of fixes on Relax NG and XInclude implementation
* Implementation of XPointer element() scheme
* Bug fixes: XML parser, XInclude entities merge, validity checking on namespaces,
  2 serialization bugs, node info generation problems, a DTD regexp generation \ 
problem.
* Portability: windows updates and path canonicalization (Igor)
* A few typo fixes (Kjartan Maraas)
* Python bindings generator fixes (Stephane Bidoul)