environmental citybuilder prototype

ktyl 47c2c189b8 tile-types (#15) ... Reviewed-on: #15		2022-12-10 18:25:00 +01:00
half-earth	tile-types (#15)	2022-12-10 18:25:00 +01:00
.gitignore	add gitignore	2022-12-03 16:26:13 +00:00
gdd.md	tile-types (#15)	2022-12-10 18:25:00 +01:00