Make NgxServerContext's log to the vhost specific logs

[oschaaf]

When a server{} block is specified in nginx.conf, that is currently not used by messages written through NgxServerContext's message handler. These still end up in the log file configured in nginx.conf at the highest level.

It would be less confusing if we respected the vhost logging configuration, and it might also be useful in the systemtests to be able to scan the vhost specific error log for unexpected (error) messages.

[oschaaf]

Fixed in 502a604