added support for large file, tested with a 3+GB instance, and some

* libxml.h include/libxml/parser.h parser.c xmlIO.c DOCBparser.c:
  added support for large file, tested with a 3+GB instance,
  and some cleanup.
* catalog.c: added a TODO
* Makefile.am: added some "make tests" comments
Daniel
diff --git a/catalog.c b/catalog.c
index 040d99c..a9dc3a4 100644
--- a/catalog.c
+++ b/catalog.c
@@ -47,6 +47,11 @@
  * TODO:
  *
  * macro to flag unimplemented blocks
+ * XML_CATALOG_PREFER user env to select between system/public prefered
+ * option. C.f. Richard Tobin <richard@cogsci.ed.ac.uk>
+ *> Just FYI, I am using an environment variable XML_CATALOG_PREFER with
+ *> values "system" and "public".  I have made the default be "system" to
+ *> match yours.
  */
 #define TODO 								\
     xmlGenericError(xmlGenericErrorContext,				\