Some non-rectangular keys are rendered incorrectly

[mjsadaway]

The RETURN key in is rendered incorrectly as .

The JSON file can be found in multistation-(sppbt).zip.

[CQCumbers]

Currently only a few special case dimensions are handled for non-rectangular keys, so if it's not an ISO return, there will be artifacts like this. A more general approach is likely possible, but I don't have the time to work on it at the moment.