Add all link headers, not just the last one

Given the way Link headers work, it does not make any sense to
just replace all other ones.  Especially when we ourselves are adding
in a loop.

plugins/WebFinger/WebFingerPlugin.php

@@ -148,7 +148,7 @@ class WebFingerPlugin extends Plugin
             $url = common_local_url('webfinger') . '?resource='.$acct;
 
             foreach (array(Discovery::JRD_MIMETYPE, Discovery::XRD_MIMETYPE) as $type) {
-                header('Link: <'.$url.'>; rel="'. Discovery::LRDD_REL.'"; type="'.$type.'"');
+                header('Link: <'.$url.'>; rel="'. Discovery::LRDD_REL.'"; type="'.$type.'"', false);
             }
         }
     }