Synchronize library description and documentation.

A note in `Foreign.JavaScrip` now indicates that the module is not intended to be used with `Graphics.UI.Threepenny`.
Acknowledge contributions by Jaap van der Plas.

The code has moved beyond the foundation by Chris Done. Thanks again!
`Foreign.JavaScript` now features a `ToJS` instance for lists, that is mapped to JavaScript arrays. #97

The implementation uses the `showList` trick from the `Show` class.