[Suggestion] Add the ability to render full-scale level holomaps

[Gesugao-san]

Description of suggestion

I propose to add the ability to render full-scale PNGs holographic maps (alike Map Renderer), a similar mechanism for which is used at the Aurora Station.

To determine the walls, the turfs can be analyzed for passability through the variable, and the inner parts can be analyzed by checking whether the turf is NOT open space or nop.

Approximate result of work (without background):

Potential use

Example of potential application: still the same → SS13 WebMap. Plus, builds itself.