Message document extracted from a COLLECT must contain all required namespaces

[petringo]

Sometimes the message document within a COLLECT document may not contain all namespace declarations, if some of them are already declared within the <collect:MeteorologicalBulletin> element. Although this is not recommended practice, it is valid. Such cases must be handled correctly, so that resulting message document contains all namespace declarations used within the document.

[petringo]

Actually, namespace declarations were in place, resulting in a valid XML document. But the xmlns attributes were not necessarily in the root element. This is what to change here.