Add a news to the home page

The website home page has an automatically filled news section.

When you want to advertize a news, add a file yyyy-mm-some-text.md under _data/news with the following structure

---
title: 'My exciting news'
date: 29 August, 2011
more_info_url: /my/url/with/more/details
effective_date: 20110829
---
Some exciting news today.

A typical example would be 2011-08-news-section.md

---
title: 'News section is up'
date: 29 August, 2011
more_info_url: /blog/2011-08-29-news-section/
effective_date: 20110829
---
The website news section is now up.

Note

We could have reused blog entries tagged #news but most of the time, the first 50 characters of a blog entry are not useful enough. So I've decided to go for the explicit _data/news structure.