CMake: add comment for openddl-parser configuration.

CMakeLists.txt

@@ -18,6 +18,7 @@ set (PROJECT_VERSION "${ASSIMP_VERSION}")
 
 set(ASSIMP_PACKAGE_VERSION "0" CACHE STRING "the package-specific version used for uploading the sources")
 
+# Needed for openddl_parser config, no use of c++11 at this moment
 add_definitions( -DOPENDDL_NO_USE_CPP11 )
 
 # Get the current working branch