The following methods have not been used any more
since the following change IDs or a commit.
* _add_vif_extension
I56d859beb675199b209587bfe0a23cd9b75233ad
* _node_dict
Ia76e41a8a3b7230701872ae7a1975edc3d9ea847
* _bdms_from_legacy and _bdms_to_legacy
I01c108ceb539bb99491ed542c683e36fbf0c2bbe
* _create_block_device_mapping
Ib0e0b708c46e4330e51f8f8fdfbb02d45aaf0f44
* _get_folder
If734e22af223836b424561e8e9ca65e6c39fe5c2
* _details_map
This method has not been used since the commit
that added the method (initial commit).
e7562217ed
Change-Id: Ica00c013961366d044f5a4ad3ed24568d60288b3