Add "namespace-node" to the reserved function names

[nobody]

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Submitted:
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Name: Gabriel Petrovay
Email: ***************
Reason: other reasons, wrong result
web site: http://experimental.zorba-xquery.com
feedbackID: 15

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Message:
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Because this is also a problem in XQuery 1.1 Draft, see:

http://www.w3.org/Bugs/Public/show_bug.cgi?id=6929

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Query:
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declare default function namespace "booo";

declare function namespace-node () {
1
};

namespace-node ()