Improved build flow and also added support of webpack/browserify

Currently this PR helps to improved build flow:

- added `@@VERSION` macro;
- removed unesesary logic (wrap with closure);

Also it solves an issue when you need to use library on different environments (`node` via `webpack`/`browserify`) vis using [UMD](https://github.com/umdjs/umd).

I have added support to different environments `eve` and you need to review [this PR](https://github.com/adobe-webplatform/eve/pull/25) before.