Set BUILD_DOCUMENTATION to OFF by default and ignore ifcopenshell python documentation generation

.gitignore

@@ -15,3 +15,4 @@ __pycache__
 /docs/output
 /docs/rst_files
 /docs/doxygen
+/src/ifcblenderexport/docs/_build

cmake/CMakeLists.txt

@@ -37,6 +37,7 @@ OPTION(IFCXML_SUPPORT "Build IfcParse with ifcXML support (requires libxml2)." O
 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(BUILD_IFCGEOM "Build IfcGeom." ON)
+OPTION(BUILD_DOCUMENTATION "Build IfcOpenShell Documentation." OFF)
 OPTION(BUILD_IFCPYTHON "Build IfcPython." ON)
 OPTION(BUILD_EXAMPLES "Build example applications." ON)
 OPTION(BUILD_GEOMSERVER "Build IfcGeomServer executable." ON)
@@ -659,12 +660,11 @@ INSTALL(TARGETS IfcGeomServer
 
 endif()
 
-
-# Documentation
-set(CMAKE_MODULE_PATH "../docs/cmake")
-ADD_SUBDIRECTORY(../docs docs)
-
-
+# Documentation	
+IF(BUILD_DOCUMENTATION)
+	set(CMAKE_MODULE_PATH "../docs/cmake")
+	ADD_SUBDIRECTORY(../docs docs)
+ENDIF()
 
 IF(BUILD_IFCPYTHON)
 	ADD_SUBDIRECTORY(../src/ifcwrap ifcwrap)