adding namespace checkings while making sure they still parse as

* parser.c parserInternals.c tree.c include/libxml/parser.h
  include/libxml/xmlerror.h: adding namespace checkings
  while making sure they still parse as wellformed documents.
  Add an nsWellFormed status report to the context, and
  provide new appropriate error codes.
* Makefile.am result/namespaces/* test/namespaces/*: add
  specific regression testing for the new namespace support
* test/att5 result/noent/att5 result/att5 result/att5.sax:
  add more coverage for the attribute parsing and normalization
  code.
Daniel
diff --git a/result/namespaces/err_8.xml b/result/namespaces/err_8.xml
new file mode 100644
index 0000000..5608312
--- /dev/null
+++ b/result/namespaces/err_8.xml
@@ -0,0 +1,2 @@
+<?xml version="1.0"?>
+<tst/>