delegate all external references to resolveExternalReference

not just only `urn:jio:` ones

jsonform.gadget.js

@@ -153,19 +153,6 @@
     return absolute_url;
   }
 
-  function downloadJSON(url) {
-    return RSVP.Queue()
-      .push(function () {
-        return jIO.util.ajax({
-          url: url,
-          dataType: "json"
-        });
-      })
-      .push(function (evt) {
-        return evt.target.response;
-      });
-  }
-
   function resolveLocalReference(schema, ref) {
     // 2 here is for #/
     var i, ref_path = ref.substr(2, ref.length),
@@ -269,17 +256,10 @@
           return mapped_url;
         });
     } else {
-      if (download_url.startsWith("urn:jio:")) {
       queue = RSVP.Queue()
         .push(function () {
           return g.resolveExternalReference(download_url);
         });
-      } else {
-        queue = RSVP.Queue()
-          .push(function () {
-            return downloadJSON(download_url);
-          });
-      }
       queue
         .push(function (json) {
           if (checkHardCircular(g, path, url)) {