Initial drop of CSSForm from the YUI3 Gallery.

This commit pulls in [CSSForm](https://github.com/tilomitra/cssforms/) from the YUI3 Gallery as of gallery-2013.03.27-22-06. The CSSForm repo can be found [here](https://github.com/tilomitra/cssforms/) with more granular commits.

This pull request introduces some small changes to CSSForm, mostly with the `meta/` and `build` file changes. The docs are empty right now, because they will probably live on YUI CSS. 

The CSS is up-to-date as of [f9c1d64d](https://github.com/tilomitra/cssforms/commit/f9c1d64da6794765f5929c06ee0b78bb84260a3c) which is CSSForm v0.2.1.

To get a sense of the CSS in this pull request, you should go to the [demo page](http://tilomitra.github.com/cssforms/).