Add option to turn off generation of Python documentation.

python/CMakeLists.txt

@@ -42,7 +42,11 @@ SET(${LIBRARY_NAME}_HEADERS
   fcl.hh
   )
 
-IF(NOT DOXYGEN_FOUND OR (APPLE AND PYTHON_VERSION_MAJOR LESS 3))
+SET(ENABLE_PYTHON_DOXYGEN_AUTODOC TRUE CACHE BOOL "Enable automatic documentation of Python bindings from Doxygen documentation")
+
+IF(    NOT ENABLE_PYTHON_DOXYGEN_AUTODOC
+    OR NOT DOXYGEN_FOUND
+    OR (APPLE AND PYTHON_VERSION_MAJOR LESS 3)) # Disable documentation on APPLE for python 2.
   SET(ENABLE_DOXYGEN_AUTODOC FALSE)
 ELSE()
   SET(ENABLE_DOXYGEN_AUTODOC TRUE)