incomplete steps for real/double support avoiding a compilation problem

* xmlschemastypes.c: incomplete steps for real/double support
* testAutomata.c include/libxml/xmlautomata.h
  include/libxml/xmlregexp.h: avoiding a compilation problem
* valid.c include/libxml/valid.h: starting the work toward using
  the regexps for actual DTD validation
Daniel
diff --git a/testAutomata.c b/testAutomata.c
index 8e65786..77e29e5 100644
--- a/testAutomata.c
+++ b/testAutomata.c
@@ -10,6 +10,7 @@
 #include "libxml.h"
 #ifdef LIBXML_AUTOMATA_ENABLED
 
+#include <libxml/tree.h>
 #include <libxml/xmlautomata.h>
 
 static int scanNumber(char **ptr) {