Apply for inclusion : fzip, ting, hexp, asset_packer

I would like to apply for inclusion on the site the following gems,

## [Ting](https://github.com/plexus/ting)

Does conversion between various phonetic representations of Mandarin Chinese, no dependencies.

## [FZip](https://github.com/plexus/fzip)

An implementation of the "zipper" data structure, used to traverse and alter tree structures in a functional, persistent way. No dependencies.

## [Hexp](https://github.com/plexus/hexp)

A DOM-like library (HTML syntax tree manipulation). It depends on Nokogiri for HTML parsing, and Sass for parsing of CSS selectors, which are both admittedly a bit heavyweight, but also focused on doing one job. Other dependencies are ice_nine and equalizer.

## [AssetPacker](https://github.com/plexus/asset_packer)

Take HTML as input, and download all mentioned assets to the local disk for off-line usage. Can be used as a standalone script, or called on a Hexp DOM. Used by [Slippery](https://github.com/plexus/slippery). Depends on Hexp and mime-types.