Fetch for Datum updates via EPSG API

[jtejido]

The Geographical Datum is fetched from a script I created a while back and realized that I haven't updated these since day 1. In order to avoid devs having to hardcode 'specific' datum (which leads to miscalculations) with updated ones (say, they only updated WGS when others have been left outdated, which leads to wrong transformations), it only makes sense to have to clean the script I initially used and upload it here on its own namespace.