Add height variations to grid

[BenKellySoftware]

Feature description
Update the map to have height using a noise map, and generate the grid to read the same map to generate its height to match. Buildings will warp to the grid so it should work fine.

Acceptance criteria/subtasks

• Update map and grid to have hills
• Set the minimum height of the camera based on where it's over so it doesn't clip in the ground

[jonjondev]

Since the change is currently out of scope, the issue is being closed until further notice.