Remove admin namespace throughout Patrole - Nova tests

In Tempest, it is meaningful to separate admin and non-admin
tests into different classes and files, because Tempest
must use clients with admin credentials to perform admin-only
API calls, like changing an admin password. More specifically,
Tempest must use the os_adm/os_admin-namespace clients
(instantiated with admin credentials) to perform these tests;
else 403s are thrown.

Patrole, on the other hand, doesn't need to use
os_adm/os_admin-namespace clients, because of the fact that
role-switching is performed to grant the os-namespace
clients sufficient credentials to perform API actions that
require admin credentials during setting up and cleaning up
test resources. Thus, the distinction between admin and
non-admin is not important in Patrole, as role-switching
means that at different points in time the clients have admin
and non-admin credentials.

Thus, all namespaces (files, folders and classes) that contain
"admin" should be renamed, if the non-admin version does not
already exist. If the admin version and non-admin version
tests both exist, then the admin version should be removed and
its tests merged with the non-admin version.

Change-Id: I4bc55c7e1c8b7391fb11baf35987ace1c4080ef1
Partial-Bug: #1672250
12 files changed