gitweb: shortlog template: removed excessive whitespace, added title bar.
The title bar is currently empty, this is just a preparation for filling it
with content.
Content-type: text/xml; charset={encoding}
<?xml version="1.0" encoding="{encoding}"?>
<rss version="2.0">
<channel>
<link>{urlbase}{url}</link>
<language>en-us</language>