Add building stages, ground tiles and details for more temperate 4x houses

[zephyris]

1. Completes all currently available 4x zoom temperate houses with building stages and ground tiles, ensures they're coded, and adds detail overlays.
2. Having established a standard within-image alignment for 4x houses and ground tiles, finalise z offset adjustment for higher zoom levels.

Kinda fixes #210

[2TallTyler]

I have no idea what your workflow does (and how you get such nice sprites from these blockout shapes), but clearly you do, and I trust that you've got it right. 🙂