Use tenant_networks_client from tempest-lib

Below files have been migrated to tempest-lib-

 * tenant_networks_client.py: Ie98ff37137e25e73eb77acb0b5b7e53184842540
 * tenant_networks.py: Ie98ff37137e25e73eb77acb0b5b7e53184842540
 * test_tenant_networks_client.py: Ie98ff37137e25e73eb77acb0b5b7e53184842540

Now Tempest-lib provides above as stable interface
so Tempest should start using those from lib and remove its own copy.

Change-Id: I51eda43e8eb30830c7641f2e38a9548c25d9f7af
diff --git a/tempest/clients.py b/tempest/clients.py
index 68c1c38..6370e2c 100644
--- a/tempest/clients.py
+++ b/tempest/clients.py
@@ -52,6 +52,8 @@
 from tempest_lib.services.compute.services_client import ServicesClient
 from tempest_lib.services.compute.snapshots_client import \
     SnapshotsClient as ComputeSnapshotsClient
+from tempest_lib.services.compute.tenant_networks_client import \
+    TenantNetworksClient
 from tempest_lib.services.identity.v2.token_client import TokenClient
 from tempest_lib.services.identity.v3.token_client import V3TokenClient
 
@@ -72,8 +74,6 @@
 from tempest.services.compute.json.server_groups_client import \
     ServerGroupsClient
 from tempest.services.compute.json.servers_client import ServersClient
-from tempest.services.compute.json.tenant_networks_client import \
-    TenantNetworksClient
 from tempest.services.compute.json.tenant_usages_client import \
     TenantUsagesClient
 from tempest.services.compute.json.versions_client import VersionsClient