"Nelson City" NZ region should be changed to "Nelson" to help prevent Geocoding errors

Geocoding does not work properly with "Nelson City" selected as the region.

Addresses are currently formatted like this:

12 Trafalgar Street
Nelson
Nelson City

This is how it should be

12 Trafalgar Street
Nelson
Nelson

This works at the moment

12 Trafalgar Street
Nelson
--

Not sure if this is due to Nelson and Tasman being unitary authorities which are part of the Nelson region - whatever the reason, it's not playing well with geocoding

Will write a patch when I get a chance