#427 Staircase - cut difference 2D and 3D view

[OK Hoff]

Related to closed ticket http://sourceforge.net/p/sweethome3d/bugs/399/

4.2 fixed the "exact height" staircase cutout (<4.2 did not show cut when staircase and floor were same height/level). There still appears to be a slight inconsistency. If a staircase "reaches" the ceiling below (but not the floor above, it will cut in the 3D view, but the stairs is not visible on upper level in the 2D view.

This may be intended, and not important. Just for the record.

ok