fix: no headers are sent if there are no headers

Author: gr2m

lib/index.js

@@ -354,7 +354,7 @@ var Client = module.exports = function (config) {
   }
 
   function getPageLinks (link) {
-    link = link.link || link.meta.link
+    link = link.link || link.meta.link || ''
 
     var links = {}