Ensure no dangling resources are left if tests are skipped

When tenant isolation is enabled, some network resources are
provisioned even though some tests are skipped. This has
a bad effect because these resources (like ip allocations,
routers and such) may have quota's default values that are
low.

With this change we ensure resources are torn down correctly.

Closes-bug:  1254166
Related-bug: 1232971
Related-bug: 1253966

Change-Id: Id86841775a26f12a5ae8c520a086e5f1ebd63135
Add test_cases for cinder cli in v2 version

Add a new test_class for cinder-cli tempest in v2 version.

 + test_cinder_volumes_list_in_v2
 + test_cinder_absolute_limit_list_in_v2
 + test_cinder_backup_list_in_v2
 + test_cinder_extra_specs_list_in_v2
 + test_cinder_quota_class_show_in_v2
 + test_cinder_quota_defaults_in_v2
 + test_cinder_quota_show_in_v2
 + test_cinder_rate_limits_in_v2
 + test_cinder_snapshot_list_in_v2
 + test_cinder_type_list_in_v2
 + test_cinder_availability_zone_list_in_v2
 + test_cinder_service_list_in_v2
 + test_cinder_transfer_list_in_v2
 + test_cinder_bash_completion_in_v2

Three command-representations are different between v1 and v2:

 = cinder list
 = cinder snapshot-list
 = cinder bash-completion

Change-Id: Ia57af3cf3d8a0e62063ade1542c086e26f041e1e
Merge "Ensure no dangling resources are left if tests are skipped"
Merge "Add test_cases for cinder cli in v2 version"