Add async initializer (which in turn bypasses queuing mess)

[natevw]

The current initialize method needs to be synchronous for "undisclosed reasons". [In short, so it can be ± compatible with another implementation that's not yet public.]

However, nothing precludes this implementation for detecting if a callback is passed in and doing different logic.

[natevw]

OOOOR, we could just use the fs.openSync method and just simplify the whole thing instead of adding more complexity…