Additional Country codes (csv included)

Hello,

I have reworked the codes found in the 'Additional country codes' sandbox module and added a few others (FAOSTAT, GAUL, UNDP, and UNI)

These are super hand for creating dynamic links and/or using the REST services these institutions provide.

I thought it might be good to include them in the module as it's only a few extra kb of data. Or at least someone else may find it useful and it saves them time.

Cheers!