plank (Elegant, simple, clean dock)

Plank is meant to be the simplest dock on the planet.

The goal is to provide just what a dock needs and absolutely nothing 
more. It is, however, a library which can be extended to create other
dock programs with more advanced features.

Thus, Plank is the underlying technology for Docky (starting in 
version 3.0.0) and aims to provide all the core features while Docky 
extends it to add fancier things like Docklets, painters, settings 
dialogs, etc.
