XhtmlBaseSink: Table caption is escaped incorrectly

Background:

We use maven-site-plugin to generate our documentation site (source is xdoc) and noticed that non-ASCII characters like Japanese or Chinese in table caption are not correctly displayed in the output html files.
During generation, these characters are encoded to entities (e.g. '和' ) and are displayed correctly in the browser.
However, in a table caption, the first '&' is escaped into '&'.
So, for example, the actual output becomes '和' while the expected output is '和'.

To verify the issue, modify org.apache.maven.doxia.sink.impl.XhtmlBaseSinkTest.testTableCaption() as follows.

    public void testTableCaption()
    {
        try
        {
            sink = new XhtmlBaseSink( writer );

            sink.table();
            sink.tableRows( null, false );
            sink.tableCaption( attributes );
            // Insert '&'
            sink.text( "cap&tion" );
            sink.tableCaption_();
            sink.tableRows_();
            sink.table_();
        }
        finally
        {
            sink.close();
        }

        // the inserted '&' will become '&' instead of '&'
        assertEquals( "<table border=\"0\" class=\"bodyTable\">" +
                "<caption style=\"bold\">cap&amp;tion</caption></table>", writer.toString() );
    }

Not sure if this is a proper fix, but I modified the following line in org.apache.maven.doxia.sink.impl.XhtmlBaseSink.write(String) ...

this.tableCaptionXMLWriterStack.getLast().writeText( unifyEOLs( text ) );

... to ...

this.tableCaptionXMLWriterStack.getLast().writeMarkup( unifyEOLs( text ) );

... and the issue was resolved without breaking existing tests.

I have attached the above modification as a patch.
Please let me know if you prefer a PR on GitHub or need more info.

Thanks in advance,
Iwao