cleanup patch from Anthony Jones fix the headers to avoid in make scan

* SAX.c: cleanup patch from Anthony Jones
* doc/Makefile.am: fix the headers to avoid in make scan
* parserInternals.c xpath.c include/libxml/*.h: cleanup of the
  includes, * vs Ptr and general cleanup
* parsedecl.py: first version of a script to extract the
  module interfaces, the goal will be to provide .decl or XML
  specification of the interfaces to build wrappers.
Daniel

DOCBparser.c

@@ -847,18 +847,6 @@ static const char *docbStartClose[] = {
 NULL
 };
 
-/*
- * The list of SGML elements which are supposed not to have
- * CDATA content and where a p element will be implied
- *
- * TODO: extend that list by reading the SGML SGML DTD on
- *       implied paragraph
- */
-static char *docbNoContentElements[] = {
-    NULL
-};
-
-
 static const char** docbStartCloseIndex[100];
 static int docbStartCloseIndexinitialized = 0;