Speed up user listing by performing parallel requests

src/js/index.js

@@ -18,6 +18,32 @@ if (search.accessToken) {
 }
 
 // poor man's async in the global namespace
+function asyncForEachParallel(items, handler, callback) {
+    var alreadyDone = 0;
+    var errored = false;
+
+    if (items.length === 0) return callback();
+
+    function done(error) {
+        // do nothing if already called back due to error
+        if (errored) return;
+
+        if (error) {
+            errored = true;
+            return callback(error);
+        }
+
+        ++alreadyDone;
+
+        // we are done
+        if (alreadyDone === items.length) callback();
+    }
+
+    for (var i = 0; i < items.length; ++i) {
+        handler(items[i], done);
+    }
+}
+
 function asyncForEach(items, handler, callback) {
     var cur = 0;