Use Tempest-lib's compute floating_ips_bulk_client

Compute floating_ips_bulk_client has been migrated to
tempest-lib- I52c0cfcbfd65e3143d608200b6cac07dac006ccc

Now Tempest-lib provides this client as stable interface so Tempest
should start using this from lib and remove its own copy.
Also remove its unit tests.

This commits makes Tempest to use compute floating_ips_bulk_client
from Tempest-lib.

Change-Id: I6d87f6056318b58f83a3be9feef3872ecf694af4
diff --git a/tempest/clients.py b/tempest/clients.py
index 2ee945d..f161ea2 100644
--- a/tempest/clients.py
+++ b/tempest/clients.py
@@ -30,6 +30,8 @@
 from tempest_lib.services.compute.flavors_client import FlavorsClient
 from tempest_lib.services.compute.floating_ip_pools_client import \
     FloatingIPPoolsClient
+from tempest_lib.services.compute.floating_ips_bulk_client import \
+    FloatingIPsBulkClient
 from tempest_lib.services.identity.v2.token_client import TokenClient
 from tempest_lib.services.identity.v3.token_client import V3TokenClient
 
@@ -41,8 +43,6 @@
 from tempest.services.baremetal.v1.json.baremetal_client import \
     BaremetalClient
 from tempest.services import botoclients
-from tempest.services.compute.json.floating_ips_bulk_client import \
-    FloatingIPsBulkClient
 from tempest.services.compute.json.floating_ips_client import \
     FloatingIPsClient
 from tempest.services.compute.json.hosts_client import HostsClient