Corner Designations

The ability to manually place corner type designations (terrain designations with 1 corner above or below others).

Done.

Considering adding a saddle type slope with one corner up and one corner down. This would allow ramps to make prettier 90 degree turns, but not sure if it excavates/dumps properly.

I would also very much love to be able to place the designations with one corner low, the opposite corner high, and the ones in between in the middle. And... A little better control over the corner designations you can make would not make me mad. :-)

Included in v0.5.10.