#1 Wrap labels in CDATA for GraphXML export

[John Gallagher]

For urls like http://someexample.com/
form.html&user=me&password=you

The GraphXML export must wrap labels in CDATA, which should be
done anyway, IMHO.

e.g. change:
<node name="506">
<label>http://someexample.com/
form.html&user=me&password=you</label>
</node>

to:
<node name="506">
<label><![CDATA[http://someexample.com/
form.html&user=me&password=you]]></label>
</node>

Fixed GraphXMLBuildingBlocks.java attached