init data_source attribution for adm0

[zackarno]

Not actually ready to be merged, but I thought rather than write a bunch of words in issue #111 , easier to just to just write some starter code in a branch to help discuss the approach. Happy to completely adjust approach and/or delete branch as we see fit.

You'll see I just implemented the approach for the Fieldmaps admin 0s as well as the first exception iso3=ABA (just put in a placeholder attribution for ABA). If we think it makes sense i can manually enter the attributions for the rest of the exceptions.

Will need to adjust this code potentially as/if we address #114 as well, but it should work in current construction of updating admins

[zackarno]

@caldwellst - This should be ready for review now.

Although it is related, I do not think we should include the switch from UN Geo Data Hub -> GAUL/Naturalearth in the PR as it's actually really complicated (and maybe less of a priority?). Therefore would be good to get what we have attributed and deal with that as a separate issue.

I went ahead and addressed #125 here because it was simple. Ideally the LAC countries would come from FieldMaps however, but to do this properly we would need to significantly restructure most of the functions in update_iso3_sf.R. The issue is that sf_world is read in as one object while iso3s from other sources are looped/mapped.

[zackarno]

Thanks for the review: all addressed 4882cbe

Should i try to run the update w/ the env var set so that it actually updates on the cloud? Or do you want to? Anything to be aware of? Should we archive the old files/store this in a different place?

[caldwellst]

Update them all! No need to archive, we will want to use this new solution and can fix any issues as they arise.