[XML-SIG] DOM test failures

[Martin v. Loewis]

With the changes to 4DOM a few weeks ago, a number of dom test cases
stopped working now. I've corrected some occurrences of empty
namespaces, but some of the remaining errors indicate genuine bugs in
the implementation.

For example, in test_node, the following sequence is executed

    p = doc.createElement('PARENT')
    if p.localName != None:
        tester.error('Error getting localName')

This test now fails, as localName is "PARENT". That appears to be in
clear violation of DOM level 2, which says

createElement
  ...

Return Value 

  Element       A new Element object with the nodeName attribute 
                set to  tagName, and localName, prefix, and namespaceURI 
                set to null.

So it seems to me that the test is right and the code is wrong. 

Comments?

Regards,
Martin

P.S. To run the DOM test suite, invoke "python test.py" in the dom
directory.