Fix dogpile.cache 0.7.0 interaction
Fix dogpile.cache 0.7.0 interaction

Due to the change in behavior in dogpile.cache > 0.7.0 where bound
methods can no longer be passed to the cache_on_arguments decorator,
openstackSDK now explicitly provides a non-method wrapper for all
elements passed to cache_on_arguments. This is handled via an explicit
no-op decorator. functools.wraps is used to preserve data from the
original method.

Needed-By: https://review.openstack.org/#/c/624993
Change-Id: Ied27fa1e834d145246815afcb67c59d48669ffb2
Story: 2004605
Task: 28502

openstack/python-openstacksdk,dtroyer/python-openstacksdk,stackforge/python-openstacksdk,openstack/python-openstacksdk,dtroyer/python-openstacksdk,stackforge/python-openstacksdk