Structure the 'Areas and teams' page with tables

[Ivorforce]

The tables are derived from the website and look like this:

This makes the design much more lean and readable, both as html and in the .rst plaintext.

I achieve this by adding a Directive extension to Sphinx, which allows us to use .. gdareatable:: with shortcuts for the various handles.

[AThousandShips]

Looks like a good improvement! And all the entries look correctly transferred, will check a second time later today