templates/rss/tagentry.tmpl

templater: clean up the process method, separating code paths

<item>
    <title>{tag|escape}</title>
    <link>{urlbase}{url}rev/{node|short}</link>
    <description><![CDATA[{tag|strip|escape|addbreaks}]]></description>
    <pubDate>{date|rfc822date}</pubDate>
</item>