keystoneclient is using apiclient.base and in order to properly
deprecate and eventually get rid of apiclient we need to move the
symbols that keystoneclient uses out of apiclient.
This change moves apiclient.base.Resource into keystoneclient.base
by merging apiclient.base.Resource into the existing
keystoneclient.base.Resource. apiclient.base.Resource is now
renaming keystoneclient.base.Resource for backwards-compatibility.
Change-Id: Id479711b7c9437aaf171def6976aab8b303ec56d