Updates the Field Item Editor to render layers based on the entire map, and the per-patch positioning of each layer.
Import/export will gracefully handle upgrade/downgrade, and viewport import/export will gracefully update tiles rather than a per-acre basis.
Performance has also been slightly improved; no allocation is done anymore when updating the image.
Allows for expansion in properties available for editing via updating Personal30's get/set list
Seems like a better compromise to only update 1 class for new additions, rather than backporting a stubbed invalid offset.
Behaves similar to WhereAreN being a nullable (optional) property.
In an ideal world, we'd have interfaces and concrete implementations for every structure revision, but that's far too much work to cleanly implement compared to the picky offset slicing.
Each player and main.dat is ~11MB of allocation to read; old would read & decrypt into separate array = 22MB * (1 + playerCount). Cutting this in half reduces the amount of allocation and keeps stuff off gen2 LOH
