* Arch: Improved ArchComponent.computeAreas function
All non vertical faces get projected now. Changed Part.Wire to DraftGeomUtils.findWires
* Arch: Removed Area property and add AreaCalculationType to Space object
The horizontal area and its perimeter are now calculated in two different ways. Eiter at the centre of mass or as a projection on the XY-plane. The results are filled in the filed horizontal area and perimeter in the Component section.
* BIM: Added property Area for Spaces again
