[Imports] Australian administrative boundaries import

[Andrew Harvey]

The Australian community have been planning an import of
administrative boundaries, we've been discussing and working on the
plan within the local community at
https://lists.openstreetmap.org/pipermail/talk-au/2018-October/thread.html.

We're at the stage now where we would appreciate an import review per
the import guidelines. All feedback/comments are most welcome.

Documentation on the import is being curated at
https://wiki.openstreetmap.org/wiki/Import/Catalogue/PSMA_Admin_Boundaries