[gobo-eiffel-develop] New serializer for XML

[Colin A. <col...@go...>]

I have completed re-factoring the code for the XSLT 2.0/ XQuery 1.0
serializer, and checked that it passes all the tests from the W3C test
suite.

This serializer can be used without running an XSLT transformation.
There is full (I believe) documentation (as part of the XSLT library
documentation), and an example of feeding the output from
XM_EIFFEL_PARSER direct to the serializer. In a similar way you could
serialize an XM_DOCUMENT.