Fix: Shut down TLS before closing socket.

We should first shut down TLS so we can signal the other end a clean shutdown
in contrast to a socket failure.

Big thanks to wget(1) to find it. Fantastic tool.

src/connection.c

@@ -1496,10 +1496,10 @@ void connection_close(connection_t *con)
     if (!con)
         return;
 
+    tls_unref(con->tls);
     if (con->sock != -1) /* TODO: do not use magic */
         sock_close(con->sock);
     if (con->ip)
         free(con->ip);
-    tls_unref(con->tls);
     free(con);
 }