fixed the initialization of the SAX structure which was breaking xsltproc

* parserInternals.c: fixed the initialization of the SAX structure
  which was breaking xsltproc
* xpath.c: patch from Petr Pajas for CDATA nodes
* tree.c: patch from Petr Pajas improving xmlGetNodePath()
* parser.c include/libxml/parser.h: patch from Peter Jones
  removing a leak in xmlSAXParseMemory() and adding the
  function xmlSAXParseMemoryWithData()
Daniel
diff --git a/parserInternals.c b/parserInternals.c
index 41725d5..c09fc95 100644
--- a/parserInternals.c
+++ b/parserInternals.c
@@ -2250,7 +2250,7 @@
     ctxt->space = &ctxt->spaceTab[0];
 
     ctxt->sax = sax;
-    initxmlDefaultSAXHandler(sax, xmlGetWarningsDefaultValue);
+    memcpy(sax, &xmlDefaultSAXHandler, sizeof(xmlSAXHandler));
 
     ctxt->userData = ctxt;
     ctxt->myDoc = NULL;