* HTMLtree.c include/libxml/HTMLtree.h: patch from Mark Vadok
  about htmlNodeDumpOutput location.
* xpath.c: removed an undefined function signature
* doc/apibuild.py doc/libxml2-api.xml: the script was exporting
  too many symbols in the API breaking the python bindings.
  Updated with the libxslt/libexslt changes.
Daniel