fix handling of multiple Content-type headers This can happen if an error happens while sending application/mercurial-0.1 content. The error page will be sent resulting (for at least lighttpd) in the following headers: Content-type: application/mercurial-0.1 Content-type: text/html which result in req.proto = 'application/mercurial-0.1, text/html' fix issue344

abort: index 00changelog.i unknown format 2!
abort: requirement 'indoor-pool' not supported!