Directive only for certain alias

[cicovy]

I just found out that it's not possible to add ssl_verify_client
directive in a "location". I received a suggestion from @kolbyjack on
the nginx IRC channel which helped me with this problem. The solution
was to deal with the $ssl_verify_client returning value.

if ($ssl_client_verify != SUCCESS) {
return 401;
break;
}

Posted at Nginx Forum: http://forum.nginx.org/read.php?2,214566,214584#msg-214584