Investigate way to deal with special case (with DWE and CPH)

[lucky-bai]

When going from CPH to DWE something weird happens: you have to go up to floor 3 of CPH, cross over to DWE (you're on the eastern half of DWE) and immediately go down to floor 2 of DWE to continue. The way I'll probably handle this (for now) is link CPH:3 to DWE:2 but this solution is not entirely satisfactory (note also you can't go from CPH:2 to DWE:2)

Problem is, we don't have a node for the eastern half of DWE, only for DWE as a whole. So where does the stair-descending take place? Not in CPH for sure, because CPH:2 is not connected to DWE:2. Doing it in DWE is confusing due to the way stair climbing is drawn on the map. So best for now is to leave out the stair-descending and link CPH:3 to DWE:2.

Later maybe we can investigate more complicated infrastructure to handle cases like this but this will do for now.

[lucky-bai]

Not going to do anything about this right now, but just a note to self: NH now has an extension that behaves the same way -- there are two "parts" of NH that are basically two separate buildings.