Update project node to reflect the actual countries module

It looks like the project node here doesn't reflect the actual countries module. Here's a first stab based on the README to get the ball rolling:

The Countries module provides a number of country related tasks:

* A countries database with an administrative interface.
* A way to alter Drupals core country list.
* A country FAPI element.
* Makes countries entities fieldable
* A countries field.

This module requires Drupal 7 and is unlikely to be backported as the majority of the implementation is not possible in Drupal 6.

*blurb about collaboration and overlap with similar modules would be helpful here*