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Just done a heavy amount of internal reorganisation. Astro-facs and bomb-facs now use the pushing code to shunt their cargo out. Originally it was the block that managed this - so this change means easier debugging, less code, and it's easier to add new features to rocks.

I've also added the ability to zoom the camera. Plus and minus keys will step the camera in and out. It's a bit wobbly due to the camera pulling math from the UI at a different resolution. When fully zoomed out you can now get as far out as 2 tiles from the edge of the generated area before you proc a new chunk.

I'm a bit back and forth on the ray-dar system. It's nice, but no substitute for actually seeing what's coming. I'm hoping the camera control is a better replacement.