fix appendfile problem on macos.
when i open file with mode 'a+' on linux, seek position is 0.
on macos seek position is end of file instead. not documented.
<div class="page_footer">
<div class="page_footer_text">#repo|escape#</div>
<a class="rss_logo" href="?cmd=changelog;style=rss">RSS</a>
</div>
</body>
</html>