cleanup, creating a new legacy.c module, made sure make tests ran in

* Makefile.am: cleanup, creating a new legacy.c module,
  made sure make tests ran in reduced conditions
* SAX.c SAX2.c configure.in entities.c globals.c parser.c
  parserInternals.c tree.c valid.c xlink.c xmlIO.c xmlcatalog.c
  xmlmemory.c xpath.c xmlmemory.c include/libxml/xmlversion.h.in:
  increased the modularization, allow to configure out
  validation code and legacy code, added a configuration
  option --with-minimum compiling only the mandatory code
  which then shrink to 200KB.
Daniel
diff --git a/xpath.c b/xpath.c
index 7946fd6..65ca180 100644
--- a/xpath.c
+++ b/xpath.c
@@ -52,6 +52,7 @@
 #include <libxml/threads.h>
 #include <libxml/globals.h>
 
+#if defined(LIBXML_SCHEMAS_ENABLED) || defined(LIBXML_XPATH_ENABLED)
 /************************************************************************
  * 									*
  * 			Floating point stuff				*
@@ -119,6 +120,8 @@
     return(trio_isinf(val));
 }
 
+#endif /* SCHEMAS or XPATH */
+#ifdef LIBXML_XPATH_ENABLED
 /**
  * xmlXPathGetSign:
  * @val:  a double value
@@ -135,7 +138,6 @@
 }
 
 
-#ifdef LIBXML_XPATH_ENABLED
 /*
  * TODO: when compatibility allows remove all "fake node libxslt" strings
  *       the test should just be name[0] = ' '