CMake: added an entry at main CMake script that makes QTViewer an optional build.
QT Viewer main structure only, libQGLViewer or any 3D functionality can be added to mainWindow as a widget later on.
- Separate IFC parsing library and geometry libraries [#3395025]
- Added example for IfcParse usage without geometry or Open CASCADE functionality
- Cleanup of vcproj Open CASCADE dependencies
- Added function to query parent class type in IfcExpressParser.py
IfcServer: first commit of a stdin/stdout interface to IfcGeomObjects [undocumented for now]
BIMserver_plugin: first commit of IfcEngine plugin implementation for use with http://BIMserver.org [undocumented for now]