faster replacement for Async

 Neo-Async is thought to be used as a drop-in replacement for Async, it almosti
 fully covers its functionality and runs faster.
 .
 Async is a utility module which provides straight-forward, powerful
 functions for working with asynchronous Javascript. Although originally
 designed for use with Node, it can also be used directly in the
 browser.
 .
 Node.js is an event-based server-side JavaScript engine.