Rotate prefabs so they face nearby roads

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This will require some extra flags on the prefab templates and some changes to the map generation.,

[rm-code]

If the map generator is done, we can provide flags for each prefabs which would tell the map generator which sides should be "street accessible".

This also means that for a non-square prefab might not be placeable, if the street accessible side is on its left, but the street is on the top side. In this case the prefab would have to be rotated in a way that couldn't fit into the prefab layout.