Update data and metadata for EV Vehicles data group

[AnaBelgun]

Electric vehicle data group https://nationalmap.gov.au/#share=s-sBgTFHguI3suZy6LOb8ZQdJEc1L

Data updates

• Average hourly and daily traffic volume (NSW) and https://nationalmap.gov.au/#share=s-tIcZao7QS8GS1VQ5upjvirSjtA7 have new APIs to connect https://data.nsw.gov.au/data/dataset/2-nsw-roads-traffic-volume-counts-api

Metadata updates for (Done by https://github.com/TerriaJS/saas-catalogs-public/pull/439)

• EV charger locations

• EV registrations by postcode

• Add (2019) to the name of each dataset

• Replace the text above "Data Description" with the following:
  This datasets has been last updated in 2019, through a project initiated and funded by the Electric Vehicle (EV) Council in collaboration with University of Technology Sydney (UTS), NSW Department of Planning, Housing and Infrastructure. Currently, there are no updates planned to this data on NationalMap. Users can access current information from the following sources:

• Electric Vehicle Council (Australia) EV Charger Map https://electricvehiclecouncil.com.au/a-z-charging/

• PlugShare global dataset https://www.plugshare.com/map/australia

• https://www.mynrma.com.au/electric-vehicles/charging/ev-charging-stations-australia

• https://evie.com.au/find-a-charger/

[AnaBelgun]

Closing as partially done. New ticket dealing with new NSW APIs here #1274