get preact files into root

src/deferred.js

@@ -0,0 +1,12 @@
+export function deferred() {
+	var d = {};
+	var promise = new Promise(function (resolve, reject) {
+		d.resolve = resolve;
+		d.reject = reject;
+	});
+
+	// Add the native promise as a key on deferred object.
+	d.promise = promise;
+	// Also move all props/methods of native promise on the deferred obj.
+	return Object.assign(d, promise);
+}