Gaia terrain example is broken

[masonwheeler]

I'm looking at Dungeon Architect, and I ran across the example scenes at https://coderespawn.github.io/dungeon-architect-quick-start-guide-unity/stage/html/quick_start_1.6.0.html

Because I have Gaia and Village Exterior Kit, I tried the scene that uses them, but I ran into multiple problems:

• The demo fails to compile because StrongholdLandscapeModifier.cs is missing multiple namespace references in its using section.
• On setting up the scene, Gaia throws multiple NREs which show up in the console. (Was this written before the major update to Gaia that came out a few months ago?)
• The landscape comes out empty because all the textures on the terrain are missing. I spoke to Blacksmith (3D Forge author) about this, and he mentioned that this is likely a known issue where Unity can fail to import terrain textures from pre-2018 versions.

Given that no version older than 2018 is currently supported by Unity, (or at least none is currently installable from Unity Hub,) could we get this fixed up to work with current versions of Unity and Gaia?