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- Use boost::optional for optional IFC arguments
- Use boost::uuid for the creation of GlobalIds
- New IfcGeomObjects setting to force alignment of TopoDS_Face normal to CCW orientation
- Removed static Ifc class, renamed to non-static IfcFile. IfcFile renamed to IfcSpfStream
- Introduced Logger class
- Introduced EntityBuffer class that keeps track of all writable entities created to add them all in once to the IfcFile class