Some minor changes.
Fixed: Issue with saving edited triangles, CadTools always claimed: "Couln't find any CadTools triangles to save (no matching X-data)".
Changed: "Tranverse 3D lines between 3D Polylines" has been changed. If elevation difference between the polylines was huge the offset din't work as expected. Offset was set to follow the transverse line direction, now it is set to follow horizontal direction.
Changed: "Polyline area" command. Added messagebox with a warning if you have 3DPolylines in your selection.
