Reordering tests under the approprite directories

Volume directories tree:
volume/admin/ -> admin tests supported v1 and v2
volume/admin/v2
volume/admin/v3
volume/ -> non admin tests supported v1 and v2
volume/v2
volume/v3

Change-Id: I8e40089e02a7816e26f5dcfda681eb895a9787f3
diff --git a/tempest/api/volume/v3/admin/__init__.py b/tempest/api/volume/admin/v2/__init__.py
similarity index 100%
rename from tempest/api/volume/v3/admin/__init__.py
rename to tempest/api/volume/admin/v2/__init__.py
diff --git a/tempest/api/volume/admin/test_volume_pools.py b/tempest/api/volume/admin/v2/test_volume_pools.py
similarity index 100%
rename from tempest/api/volume/admin/test_volume_pools.py
rename to tempest/api/volume/admin/v2/test_volume_pools.py
diff --git a/tempest/api/volume/admin/test_volume_type_access.py b/tempest/api/volume/admin/v2/test_volume_type_access.py
similarity index 100%
rename from tempest/api/volume/admin/test_volume_type_access.py
rename to tempest/api/volume/admin/v2/test_volume_type_access.py
diff --git a/tempest/api/volume/admin/test_volumes_list.py b/tempest/api/volume/admin/v2/test_volumes_list.py
similarity index 100%
rename from tempest/api/volume/admin/test_volumes_list.py
rename to tempest/api/volume/admin/v2/test_volumes_list.py
diff --git a/tempest/api/volume/v3/admin/__init__.py b/tempest/api/volume/admin/v3/__init__.py
similarity index 100%
copy from tempest/api/volume/v3/admin/__init__.py
copy to tempest/api/volume/admin/v3/__init__.py
diff --git a/tempest/api/volume/v3/admin/test_user_messages.py b/tempest/api/volume/admin/v3/test_user_messages.py
similarity index 100%
rename from tempest/api/volume/v3/admin/test_user_messages.py
rename to tempest/api/volume/admin/v3/test_user_messages.py