Previously, the functions in article_location.rs where returning generic
anyhow::Result.
In order to ease error handling when using the library, it have been
moved to specific errors.
A basic chabot application that downloads article from one newspaper
have been added.
It can download html pages and is called with !hmtl
ArticleLocation have been refactored to own it's internal data.
A first example as well as some documentation have been added
The first example builds an article location and download the article as
an html String.
The documentation explains how it has been designed and what is the goal
of the application as well as it's intended architecture
