#179 Reduce Log Clutter by Downgrading Msg from E_WARN to E_DEBUG

[Joseph D. Wagner]

Change line in upnphttp.c from:
DPRINTF(E_WARN, L_HTTP, "HTTP Connection closed unexpectedly\n");
to:
DPRINTF(E_DEBUG, L_HTTP, "HTTP Connection closed unexpectedly\n");

So many clients tigger this error that it just clutters the logs unless debugging.

I tired to submit this via git, but I got an access denied message. I am new at this, so I may have done something wrong.

[Shrimpkin]

Or just change log level to error in minidlna.conf.