Example updated to ES6 syntax

[ImranMH]

[ImranMH]

Those examples are too old not since es6 now implemented everywhere

[wesleytodd]

For reference: #3427

My opinion on this is stated there, but both of these PR's are failing tests, so this might not be an acceptable change until we update the tooling to support new es2015 syntax.

[wesleytodd]

@dougwilson It appears I am still unable to add the proper tags here. Is there a permission you need to give me?

[anlexN]

@express team, please rewritten codebase in es2015+