Added Australia map with 7 bots and their flags (#306)

This is a map of the Australian country. It has 7 bots - the 7 states of
the country. This is my first time making a pull request, so I'm sorry
if i messed something up or something doesn't work.

src/scripts/generateTerrainMaps.ts

@@ -17,6 +17,7 @@ const maps = [
   "SouthAmerica",
   "Britannia",
   "GatewayToTheAtlantic",
+  "Australia",
 ];
 
 async function loadTerrainMaps() {