preparing release of libxml2-2.6.3, updated and regenerated the docs.

* configure.in doc/* libxml.spec.in: preparing release of
  libxml2-2.6.3, updated and regenerated the docs.
Daniel
diff --git a/libxml.spec.in b/libxml.spec.in
index 5f50a99..24a70d0 100644
--- a/libxml.spec.in
+++ b/libxml.spec.in
@@ -62,6 +62,7 @@
 %build
 %configure
 make
+(cd doc/examples ; make clean)
 
 %install
 rm -fr %{buildroot}