Make "chunkedlen" test server command output final CRLF after chunked data.
Update a couple of test cases to output the final CRLF.

Fixes: #780



git-svn-id: http://www.varnish-cache.org/svn/trunk/varnish-cache@5476 d4fa192b-c00b-0410-8231-f00ffab90ce4