* SAX2.c, encoding.c, error.c, parser.c, tree.c, uri.c, xmlIO.c,
  xmlreader.c, include/libxml/tree.h: many further little changes
  for OOM problems.  Now seems to be getting closer to "ok".
* testOOM.c: added code to intercept more errors, found more
  problems with library. Changed method of flagging / counting
  errors intercepted.