Generate site document via Doxia Sink API

[kwin]

Similar to https://issues.apache.org/jira/browse/MPLUGIN-442 the Site document should be generated with the help of the Doxia Sink API instead of using the (legacy) intermediate XDoc format.

modello/modello-plugins/modello-plugin-xdoc/src/main/java/org/codehaus/modello/plugin/xdoc/XdocGenerator.java

Line 70 in 9b59b52

public class XdocGenerator extends AbstractXmlGenerator {