osutil.c: include Python.h before the other headers
This is recommended by the Python documentation, since Python.h defines
some constants.
#header#
<!-- Changelog -->
<id>{urlbase}{url}</id>
<link rel="self" href="{urlbase}{url}atom-log"/>
<link rel="alternate" href="{urlbase}{url}"/>
<title>#repo|escape# Changelog</title>
#latestentry%feedupdated#
#entries%changelogentry#
</feed>