Normalize OpenID URI before checking it for validity

Fixes #251

plugins/OpenID/openid.php

@@ -131,6 +131,7 @@ function oid_check_immediate($openid_url, $backto=null)
 
 function oid_authenticate($openid_url, $returnto, $immediate=false)
 {
+    $openid_url = Auth_OpenID::normalizeUrl($openid_url);
     if (!common_valid_http_url($openid_url)) {
         throw new ClientException(_m('No valid URL provided for OpenID.'));
     }