This version splits the geometry interpretation process into two steps (a) map IFC to a smaller set of schema-agnostic definitions (ifcopenshell::geometry::taxonomy) (b) convert these into explicit breps or polyhedra with Open CASCADE or CGAL.

Three validation options are added to IfcConvert for (a) storey containment (b) wall connectivity (c) space boundaries.

In good time this will be merged into the upstream IfcOpenShell v0.7.0 branch.

Daily developer testing build blenderbim-210523