Fix callers to file.revision to use file.read
This was causing unchanged files to show up as modified.
<item>
<title>#desc|firstline|escape#</title>
<link>#url#?cmd=file;file=#file#;filenode=#filenode#</link>
<description><![CDATA[#desc|escape|addbreaks#]]></description>
<author>#author|obfuscate#</author>
<pubDate>#date|rfc822date#</pubDate>>
</item>