download _gda2020.zip file

[mtmail]

Sometime in 2019 the data.gov.au started publishing multiple files, which broke the dataURL= assignment.

curl -sL 'http://www.data.gov.au/api/3/action/package_show?id=19432f89-dc3a-4ef3-b943-5326ef1dbecc' | jq -r '.result.resources[] | select(.format == "ZIP") | .url'
https://data.gov.au/data/dataset/19...2f/download/may20_gnaf_pipeseparatedvalue.zip
https://data.gov.au/data/dataset/19...2a/download/may20_gnaf_pipeseparatedvalue_gda2020.zip
https://data.gov.au/data/dataset/19...33/download/documents.zip

I hope http://www.gda2020.com.au/ is safe to be the new default.

Also added wget --no-clobber because if a build breaks during download a restart would instead download to new file with ".1" or ".2" appended.