Work on python wrapper

cmake/CMakeLists.txt

@@ -25,7 +25,6 @@ OPTION(UNICODE_SUPPORT "Build IfcOpenShell with Unicode support (requires ICU)."
 OPTION(COLLADA_SUPPORT "Build IfcConvert with COLLADA support (requires OpenCOLLADA)." ON)
 OPTION(ENABLE_BUILD_OPTIMIZATIONS "Enable certain compiler and linker optimizations on RelWithDebInfo and Release builds." OFF)
 OPTION(IFCCONVERT_DOUBLE_PRECISION "IfcConvert: Use double precision floating-point numbers." ON)
-OPTION(USE_IFC4 "Use IFC 4 instead of IFC 2x3 (full rebuild recommended when switching this)" OFF)
 OPTION(BUILD_IFCPYTHON "Build IfcPython." ON)
 OPTION(BUILD_EXAMPLES "Build example applications." ON)
 OPTION(USE_VLD "Use Visual Leak Detector for debugging memory leaks, MSVC-only." OFF)
@@ -488,14 +487,6 @@ if(COMPILE_SCHEMA)
         list(REMOVE_ITEM IFC_RELEASE_NOT_USED "4")
         add_definitions(-DUSE_IFC4)
     endif()
-else()
-    if(USE_IFC4)
-        add_definitions(-DUSE_IFC4)
-        set(IFC_RELEASE_NOT_USED "2x3")
-    else()
-        add_definitions(-DUSE_IFC2x3) # TODO Make all caps? i.e. USE_IFC2X3
-        set(IFC_RELEASE_NOT_USED "4")
-    endif()
 endif()
 
 # Boost >= 1.58 requires BOOST_OPTIONAL_USE_OLD_DEFINITION_OF_NONE to build on some Linux distros.